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About Google Book Search Google's mission is to organize the world's information and to make it universally accessible and useful. Google Book Search helps readers discover the world's books while helping authors and publishers reach new audiences. You can search through the full text of this book on the web at |http : //books . google . com/| LlWMRY r BLOCK SIGNAL OPERATION A. PRACTICAL MANUAL BY . WM. L pERR BUFEBINTENDENT DELAWARE DIVISION OF THE EbIB RaILBOAD SECOND EDITION. D. VAX NOSTRAXD COMl>^\JVY. PUBLISHERS , 23 Murray and 27 Warren Streets j 1902. CtoFTUOBT, 1897, BT D. Van NonaiAHD Oow \ Hi 'A ' A \ ^ ^^ PREFACE ^ In submitting this work to the raihroad and engineering public the writer Q .1 wishes to disclaim any thought of proposing original ideas, his aim being simply to present the latest practice in block signal operation that obtains in this country and in Europe. The only pretension to originality is in connection with " A Method of Single Track Blocking " described iu Chapter X., which, it is believed, embodies features that will ensure the holding, at the proper passing sidings, of trains to be met by opposing trains. Neither is any attempt made to discuss the relative merits of the different systems of blocking, nor to give more than a general descrip- tion of the apparatus used in carrying out the block principle, except where details seem to be necessary to a proper understanding of the operating rules. c3 OO-^-^/^ 5 O PREFACE. As the block system has been in use in England almost from the beginning of railroads, the English practice of to-daj is the result of a long experience by which the railroads of this country should not fail to profit, and on this account some- what more space is devoted to English rules and methods than would otherwise seem necessary. Thanks are due and are gratefully extended to the following gentlemen who have furnished much of the information contained in these pages : Mr. Geo. P. Neele, ex-Superintendent of the line, London & North Western Railway ; Mr. Edgar Van Etten, General Superintendent, New York Central & Hudson Kiver Bailroad ; Mr. Charles R. Fitch, General Superintendent, Erie Railroad ; Mr. C. H. Piatt, General Superintendent, New. York, New Haven & Hartford Railroad ; Mr. O. M. Shepard, Superintendent, New York, New Haven & Hartford Railroad ;. Mr. Heniy Johnson, of the Standard Railroad Signal Company ; Mr. Wm. P. Hall, President, and Mr. W. W. Salmon, Engineer and Western Agent of the Hall Signal Company; Mr. A. W. Sullivan, General Superintendent, Illinois Central PREFACE. Railroad ; Mr. Geo. H. Paine, formerly General Agent of the Union Switch & Signal Company ; Mr. W. H. Canni£f, General Manager, Lake Shore & Michigan Southern Eailway ; Mr. E. F. Brooks, Superintendent, Pennsylvania Railroad ; Mr. Dwight C. Morgan, Consulting Engineer to Railroad and Warehouse Commis- sion of the State of Illinois; Mr. Charles Hansel, Vice-President & General Mana- ger, National Switch & Signal Company. Assistance in the arrangement and re- vision of the material, and in its preparation for the press, has also been rendered by Mr. E. E. Russell Tratman, Assoc. M. Am. Soc. C. E. PoBT Jervis, N. T., U. S. a., February y 1897. LIST OF ILLUSTRATIONS. Dia£;ram of Signalling and Track. • - - - - Semaphore Block Signal and Tower ..... Blocking at a Single Track Railroad Croaaing ... Blocking at a Double Track Railroad Oroeainp^ ... Blocking at a Single and Doable Track Junction ... Blocking at a Double Track Junction .... Blocking at a Double Track Triangular Junction ... Blocking and Interlocking at a Double Track Quadrangular Junction. Single ^ack Grosaing ...?... Double Track Oroasing ...... Double Track Junction ....... Junction of a Single and Double Track .... Double Track Triangular Junction ..... Fletcher's Combined Block Telegraph Apparatus and Bell Junction on the London & Nortii Western Railway ... Lap Siding -.-.-... SignaJa and Tower on the New York Central & Hudson River Railroad Connection and Insulation of Rail Circuit at Track Joints Hall Automatic Signal ....... Webb & Thompson Train Staff Machine .... FAOK. Inset between 22 & 23 - 38 53 . 68 64 - 66 66 Inset between 60 &'61 - 70 71 - 72 73 . 76 83 - 96 169 - 170 186 - 191 203 CONTENTS. CHAFE1SB. I. INTBODUOTOBT.^Time Table, Train Dispatching, Train Sheet, Doable Order System, Time Limit System and its Defects ; Block Principle, Sketch of the History of the Block System, Adoption by American Lines, Item of Expense. n. GENEBAL PBINGIPLES.— Definition of Block Signalling, Length of Blocks, Non- following and Non-meeting Block, Different Systems, Advantages, Absolute and Permissive Blocking, Flagging and Protection of Trains, Definitions of Signals. m. BLOCK SIGNALS. — ^Location ; Semaphore, Banner and Disk Signals ; Home, Advance and Distant Signals, Signal Levers and Connections, Interlocking of Levers, Selector, Compensator, Back Lights, Bepeater, Methods of Placing Signals, Short Blocks, Colors, Electric Slot, Mechanical Slot. IV. SIGNAL LAMPS. --Care of Lamps, Light Commutator. n. CONTENTS. CHAPTER. V. BLOCK TOWER— Office, Wiring, Heating. VI. SIGNAL BELLS.— Circuits, Bell Apparatus, Use, Failures. VIL BLOCK RECORD. Vin. TRAIN ORDERS AT BLOCK STATIONS.— Train Orders and the Block Signal. IX. BLOCKING AT JUNCTIONS AND RAILROAD CROSSINGS.— Principles, Requis- ites, Interlocked Signals, Derails, Special Instructions, Arrangement of Signals, "Back-up" Movements, Interlocking Mechanism, its Principle and Rules for Constructing and Operating ; Examples. X. MANUAL BLOCKING. — English Instruments and Practice, Rules of the London and North Western Railway, Warning Arrangement, Equipment of Erie Railroad, Rules of the Erie Railroad ; Mozier System ; Obstruction Danger Signal, Crossing Over to Opposite Track ; A Method of Single Track Blocking, Intermediate Blocks, Bell Signalling, Using Siding, Mode of Operation, Lap Siding ; Rules of the New York, New Haven and Hartford Railroad Governing Use of Outlying Sidings. XI. CONTROLLED MANUAL BLOCKING.— Auto-manual Blocking, Mode of Operating, Sykes, Patenall and Union Lock and Block Instruments, Elective Slot, Requisites, Equipment and Rules of the New York Central and Hudson River Railroad for Four-track Signalling. CONTENTS. m. CHAFTER. XIL AUTOMATIC BLOOKINQ.— How Operated, Track Circuit, Normal Safety and Nor- mal Danger Plans, at Junctions, etc., Electro-pneumatic System, Bules of the Pennsylvania Bailroad for Operating Electro-pneumatic System, Electric System, Bules of the Lake Shore and Michigan Southern Bailway for Operating Electric Signals, Bules of the Illinois Central Bailroad for Operating Electric Signals. XHL MACHINE BLOCKING.— Principles, Pilot Guard, Tram Staff, Electric Train Staff Machine, Train Tablet Machine, Exchanging Device, Bules of the London and North Western Bailway, Bules of the Chicago, Milwaukee and St. Paul Bailway. XIV. APPENDIX. — Use of Fixed Signals for Protecting Maintenance of Way Operations, Pilot Working when One Track of a Double Track is Obstructed. INDEX. CHAPTER 1. INTBODUCTORT. Trains are ordinarily moved according to a "time-table," which is "the general law governing the arriving and leaving time of all regular trains at all stations." Before a train leaves its starting point, however, the dispatcher is notified by telegraph, so that he can issue special telegraphic orders to the train if this is desirable. Trains are directed by such telegraphic orders whenever it is deemed advisable to depart from the ordinary rules and the time-table, as for instance, when a train on single track faUs behind its regular schedule, and thereby fails to reach a time- table meeting point at the scheduled time. In order to prevent delay to the oppos- ing train or trains the meeting is changed from the scheduled point to a more 2 BLOCK SIGNAL OPERATION. coDYenient one, by special orders addressed to those in charge of the trains affected. Another case is when a superior train on either double or single track becomes late. To prevent delay by other trains waiting for the overdue train, the latter is directed by special orders to run a certain time later than its regular time sched- ule, the dispatcher having set back (for that day) the schedule of the train between the points named for a certain time stated in the orders. Copies of the orders are given to other trains, so that these can be governed by the later time instead of by the regular schedule. Other cases calling for the use of special orders are those of the passing of a fast train around a slower one, both moving in the same direction ; the governing, with reference to other trains, of the movements of work trains or other irregular trains ; and the governing of any other irregular movements. This method of directing the movements of trains is called " train dispatching.'* The dispatcher keeps a record of each train on what is known as the " train sheet." This record consists of the number of the train and of the engine, the names of the conductor and engine-man, the number of each kind of cars in the train, the time of the train's departure from the starting point, of its an'ival and INTRODUCTORY. 3 departure at the piincipal intermediate stations and of its arrival at the destination. By the train sheet, therefore, the dispatcher can at ail times quickly locate the train and determine the time that it will probably arrive at a distant station. Under the " double order system," which is considered to be by far the safest method of train dispatching, each person or train affected by an order receives a copy of it, or, in the words of the standard code, "each order must be given in the same words to all persons or trains directly affected by it, so that each shall have a duplicate of what is given to the others." So strictly is the dupli- cation of orders carried out in this method that an operator must, in case he did not originally make a sufficient number of copies at one time, trace from a copy which has been approved by the dispatcher the additional copies required. A few of the other principal points governing the issuing of telegraphic train orders under this method are as follows : The orders must not contain instructions not essentially a part of them. They must be brief and clear. They must be addressed to those who are to execute them, naming the place at which each is to receive his copy ; each person addressed must be supplied with a copy. Orders once in effect continue so until iul- 4 BLOCK SIGNAL OPERATION. • filled, superseded or annulled. The delivery of orders to those who are to execute them carries with it permission to pass the train-order signal at ''danger" at that point, but docs not confer any right to pass the block or other signals at " danger." The '* time-limit system " is a method of keeping trains a certain length of time apart, and is so named in contradistinction to the "block system," which k^eps trains ii certain distance apart. By the time-limit system a train is held at a station a certain time behind a preceding train, the procedure under the standard code ol the American Bailway Association being as follows : When a train of inferior class meets a train of superior class on single track, the train of inferior class must take the siding and clear the train of superior class five minutes. A train of inferior class must keep five minutes off the time of a train of superior class following. Passenger trains running in the same direction must keep not less than five minutes apart. Freight trains following each other must keep not less than five minutes apart. On many roads the minimum time between trains is extended, usually to ten minutes. The time-limit system is defective in that it presupposes a machine-like regu* INTEODUGTORY. 5 larity in the movement of trains, which does not and cannot exist. In itself it affords little or no protection to slow trains against being overtaken between sta- tions bj fast trains. But its especially weak point on single track is that it offers no safeguard worth mentioning for head-to-head movements, and none whatever against error in or misunderstanding of orders in regard to irregular meeting points. The absolute block system does protect trains under these circumstances, by keep- ing them a certain distance apart In viewing the subject of block signalling in a general way, care must be taken not to confound the instruments for carrying out the block principle with the principle itself. Broadly speaking, the block system, or what would seem a more appropriate name, the space system, is the maintaining of a space between trains while running on the line. The actual operation of the block system dates from December, 1839, when the Great Western Railway, of England, began telegraphing the arrival and departure of its trams from station to station for a short distance, near London. This was at the suggestion of Messrs. Oooke and Wheatstone, who, in 1841, intro- 6 BLOCK SIGNAL OPERATION. duced separate instruments for each direction of traffic, showing whether the sec- tions were clear or blocked. They also added telegraph bells. The first well-authenticated published suggestions of the block system were contained in a pamphlet printed in 1842, entitled " Telegraphic Railways," by Mr. (afterwards Sir) W. F. Cooke, an English engineer. He laid down the follow- ing principles : " Every point of a line is a dangerous point, which ought to be covered by signals. The whole distance, consequently, ought to b3 divided into sections, and at the end as well as the beginning of them, there ought to be a signal, by means of which the entrance to the section is opened to each train when w^e are sure that it is free. As these sections are too long to be worked by a traction rod tliey ought to be worked by electricity. At the end of each section cf from two to two and a half miles, a line-keeper is stationed in a hut, with a turning disk, or a semaphore. In each hut there ought to be two telegraphs with magnetic needles, the one on the right hand being in communication with that on the left of the neighboring hut. The needle telegraph can only give two signals: * Line clear,' or * line blocked.'." INTRODUCTORY. 7 It will be noted that this embodies all the leading features of the block systems of to-day. The constantly increasing volume of business on railroads soon made it necessary to improve the means for securing safety in operation, and in 1851 Mr. C. V. Walker, of the South Eastern Railway, of England, devised the method of signalling by electric bells, the signals being by sound only, no needle instruments being used. In 1854 the London & North Western Bailway introduced separate instruments for each track, with three positions of the needle, and later used the bell code in connection therewith. Subsequently automatic block signals were in- vented and brought into use, and they are now used more extensively in the United States than in any other country. The Sykes system of block signalling was invented in 1875. In this method the out-door signals at a block station are controlled by the signal-man at the station in advance, by means of electrically-operated locks, the locking apparatus at the two stations being connected by an electric circuit. This effects a decided check against mistakes or carelessness, for while each signal-man operates his own signals, he cannot operate them uutil they have been unlocked by the signal-man in advance, on request of the first signal-man. 8 BLOCK SIGNAL OPERATION. The block system was introduced into the United States by the Pennefylvania Baibroad about 1876, and has since been adopted in whole or in part by the Erie, the New York Central & Hudson Biver^ the Chicago, Milwaukee & St. Paul, the Illinois Central and other railroads. It is also used on many raih-oads for the pro- tection of junctions, draw-bridges, etc., and of parts of the line where there are heavy descending grades or sharp curves. It is hardly in the province of a work of this kind to consider in detail the question of which of the different types of blocking is best suited to a particular situation. At junctions, and at railroad crossings at grade, where there are interlocked switches and signals the manual type will probably be operated, because of the necessity of having an attendant to operate the track switches (points) and signals, which should be operated in unison with the block system, no matter which type is used. At passing sidings on single track lines the manual type will be used, be- cause it is necessary always to have a distinct understanding between persons at different passing sidings as to whether it is all right for a train to make a contem- plated movement. INTRODVCTORY, 9 The manual type requires the constant employment of an attendant at each block station to operate the signals, and of a small force to inspect and maintain the signals at the different stations. In hours when the traffic is light, however, as at night, some of the block stations can be closed. The consequent saving in attendants' wages is considerable, and the only effect on the service is that the blocks, being longer, take more time to clear. In the manual type comparatively expensive station buildings have to be provided, for housing the attendant and the signal machinery. The following are items of expense in the manual type : Block station build- ings ; electric bells with keys, batteries and wire circuits for code signalling between the different stations, and between stations and outlying switches ; out- door signals, including the posts, signal levers, interlocking, foimdations, signal wires with pulleys, stakes and posts for supporting the wires, and signal wire com- pensators ; and, when used, electric locking apparatus, including the wire or the track circuit, for controlling the out-door signals. The out-door signals should be a distant and a home signal for each direction at points where there are no cross- overs or passing sidings, and a distant, home, and an advance signal for each 10 BLOCK SIGNAL OPERATIOK direction where there are cross-overs. Where there are passing sidings additional signals are required to goyem the moYements of trains from the siding into the block in advance. Signal repeaters for indicating to the signal-man the position of signals located out of his sight should be taken into account. In addition to these items of expense are wages of attendants, of inspectors and of linemen, cost of fuel and of material used in repairs and renewals, and interest on cost of plant. In machine blocking the staff or tablet machines form an additional item of exnense. In estimating the cost of an automatic system these items of expense should be taken into consideration : Signals ; electric circuits (track or wire) ; batteries ; battery houses ; track instruments for making and breaking the controlling oper- ating circuit if a wire circuit is used ; switch (point) instruments for connecting th(^ switches with the signal circuit, so that when a switch is set for the side movement the signal circuit is broken and the block signal falls to " danger ;" switch, indicators, to be placed at switches to indicate to trains on sidings the con- dition of the blocks ; instruments for so operating the block signal, as to protect a point where the main track is broken in the ooarae of business, as at draw-bridges. INTBODUCTOBT. 11 etc., by controlling the operating circuit ; and battery sapplies and other material used in the repairs and renewals of the plant. While attendants are not required to operate the signals in the automatic type, the employment of a corps of experi- enced linemen is necessary to keep the line and instruments in repair, renew the batteries, etc. There should also be taken into account the wages of an electrician, battery men, and of inspectors of the electrical apparatus, and the interest on the cost of the plant. If compressed air is used the following items are to be added : com- pressor engines and the necessary steam or other plant for running them ; fuel, oil, etc., for the engines; piping for conveying the compressed air to the different block stations ; and (for operating the signal blades) air cylinders with electrically-con- trolled valves for governing the admission of the compressed air. In comparing the cost of the different systems of block signalling each item on account of construction, maintenance and operation must be considered. The first thing to be determined is the number of blocks into which the line is to be divided. It is estimated that a train running at the rate of 100 miles an hour requires a space of '2,500 feet in which to come to a stop, and as this speed is now very generally looked upon as the ideal speed to be aimed at, and has, in fact, been 12 BLOCK SIGNAL OPERATION. actually attained in a few instances, it may have to be taken into consideration when arranging a block signal plant. Trains ninning at that speed would require the blocks to be at least nearly a half mile long. On the other hand, where the speed is lower, and especially in yards where trains are numerous but run at com- paratively low speed, shorter blocks are desirable. In all types of blocking the cost of interlocking for junctions and crossings is the same, if ordinary manual interlocking is used ; therefore this item does not €iffect the comparative cost of the different systems of block signalling. CHAPTER II. GENEBAL PKINCIPLES. The block system is a method of keeping trains a certain distance apart. Under it the line is divided into blocks, or sections, the entrances to which are guarded by appropriate signals for the government of trains. The blocks may be of any reasonable length, depending on the physical characteristics of the line and on the amount of traffic — that is, the frequency with which trains are run. On lines with heavy traffic the blocks are often not more than a few hundred yards long, while with lighter traffic they may be from three to eight miles in length. They must not, however, be so short that the distant signal governing a block will over- lap a signal of the next block in the rear, if this distant signal is so placed as to give a train a sufficient distance in which to make a stop before reaching the home U BLOCK SIGNAL OPERATION. signal governing the block. For non-meeting purposes on single-track lines the blocks extend from one passing siding to another. The same principles that govern double track blocking largely govern blocking on single track. In double track blocking, however, only the movements of trains in following each other have to be provided for, while single track blocking has to do this, and, in addition, guard against trains meeting head-to-head. Therefore, double track blocking may be distingtdshed by the general name of *' non-follow- ing block," in contradistinction to that of " non-meeting block," for single track blocking. The block systems generally used are the " manual," " controlled manual," " auto-manual," " automatic," and "machine." In manual blocking the block, or out-door, signals at the entrance to each block are wholly controlled and operated by the signal-man at that station. In controlled-manual blocking the block signals at the entrance to each block are controlled either electrically, as in the Sykes system, or mechaniciilly, by the signal-man at the station in advance, but are operated by the signal-man at the entrance to the block. GENERAL PRINCIPLES. 15 In the auto-manual system the signals are in general operated as in the manual, or as in the Sykes, but are replaced in the " danger " position automati- cally by the train after the rear car passes them. In automatic blocking the operation of the signals is entirely automatic, gen- erally through the agency of electricity, or of a combination of electricity and com- pressed air. With this system, therefore, no signal-men are required. Machine blocking is a method of controlled single track blocking in which are used, in connection with the ordinary out-door signals, certain machines with de- tachable parts and worked mechanically, except that they are unlocked electrically* The principal benefits from the block system are increased safety for trains and economy and increased faciUty in train operation. Increased safety is gained in three ways : (1) By keeping trains on the road an invariable distance apart, thus reducing to a minimum the risk of coUision, either from trains overtaking each other, or opposing trains meeting on single track ; (2) by the employment of signal-men, who have a full view of passing trains and of the tracks for a considerable distance, and being in regular communication with the track walkers and other watchmen, are often able to stop trains in time to 16 BLOCK SIGNAL OPERATION. save serious trouble from defective train appliances and road-bed ; (3) by train- men and engine-men using greater vigilance, being alert at all times for signals, which, under the block system, are comparatively close together. Switching on the main track, especiaUy by switch engines in busy yards, is one of the prin- cipal sources of accidents on a railroad, and the efficiency of any system of block signalling may be measured by its capability to prevent accidents from this source. Economy and increased facility in the operation of the train service are en- sured by the fact that irregular trains are prevented from doubling up and causing blockades at passing and other points where track room is limited. They also follow from the greater uniformity in the arriving of irregular trains at terminals, which distributes more evenly the yard work of handling cars and power, and thereby also reduces traffic expenses, as the yard work can then be done more economicaUy than when there is a rush at one time and a standstill at another. With the block system most of the irregular movements of trains can be di- rected without the use of special orders, and with greater promptness, each block being in charge of a man who is on the spot and is familiar with the situation, and GENERAL FBINCIPLES. 17 to whom the dispatcher can give many orders relative to the movements of trains at that point, which orders wonld otherwise have to be addressed to the conductors and engine-men. This particular advantage is, of course, not obtained by the use of the automatic block system. '' Absolute blocking " is the method of operation in which two trains are never allowed to be on a block section at the same time. In other words, one train must not be allowed to enter the block until the preceding train has passed on to the next block. '' Permissive blocking" is a so-called form of blocking in which a train is allowed to enter a block before the preceding train has passed out. It is not block- ing in the strict sense of the term, and by its use the fundamental principle of blocking — the keeping of trains a certain distance apart — ^is destroyed. The " time- limit " system is usually operated in connection with it. The running of trains under absolute blocking does not in any way dispense with other methods of protection, such as flagging, etc., which are laid down in the standard code or other train rules. It must not be assumed, because only one train at a time is ordinarily allowed 18 BLOCK SIGNAL OPERATION. in a block, that only one can enter, for circumstances may arise making it neces- sary to admit a second train, such as a wreck train or an engine sent to the assist- ance of the preceding train in case of an accident. This, however, is an exceptional condition which does not affect the principle of operation for the regular traffic or train service. The following are the American Bailway Association's definitions of inter- locking and block signals, as revised by its Joint Committee, February 20 and 21, 1896. Block. — A length of track of defined limits, the use of which by trains is controlled by block signals. Block Station. — The office from which block signals are operated. Block Signal. — A fixed signal controlling the use of a block. ^07716 Block Signal. — A fixed signal at the entrance of a block to control trains in entering and using said block. Distant Block SignaL— A fixed signal of distinctive character used in connection with a home block signal to regulate the approach thereto. Advance Block Signal. — A fixed signal placed in advance of a home block GENERAL PRINCIPLES. 19 signal to provide a supplemental block between the borne block signal and the advance block signal. Block System, — A series of consecutive blocks controlled by block signals. Telegraph Block System. — One in which the signals are operated manually upon telegraphic information. Controlled Manual Block System. — One in which the signals are operated manually, and by its construction requires the co-operation of the signal-men at both ends of the block to display a clear signal. AidoTfiatic Block System. — One in which the signals are operated by electric, pneumatic or other agency, actuated by a train or by certain conditions affecting the use of a block. CHAPTER III: THE BLOCK SIGNAL. * In laying out a block signal system a careful study of the line should be made on the ground, with respect to the locating of the block stations, special attention being given to junctions and yards. By block station is meant the position of the home signal or the signal tower which marks the actual point of division between the blocks. It has no reference whatever to the railroad station. Under the auto- matic system the block station has no visible indication, being merely an insulated joint in the track at some little distance from the signal itself. The following con- siderations may be of assistance in selecting the best location for a signal, but any case may require a special arrangement, which can only be determined on the spot. Signals should be located at the most prominent points in the neighborhood — THE BLOCK SIGNAL. 21 that is, the points first seen on approaching the block station. Economy in first cost should not interfere with placing them in the most conspicuous positions. They should be located sufficiently distant from crossings with other railroads and from junctions, sidings and cross-overs, to give trains ample room to stop between the signal and the dangerous point which it protects. They should be located at the right of the main track, as viewed from approaching trains. Their elevation above the track should not, if possible to avoid it, exceed thirty-five feet, nor in the case of main line signals, be less than fifteen feet. Signals that are very high are often enveloped in fog or snow or otherwise obscured when a lower signal could readilv be seen. The best position for a block station ought rarely to be n^lected for the sake of locating at a traffic station. Better results are obtained by placing the block sta- tion where it ought to be, than by favoring a traffic point where only a short distance view of the signals can be had. There should be block signals at all junctions, railroad crossings at grade, ends of yards, cross-overs, passing sidings and draw-bridges, so that the movements of trains at such points will be well protected. The handling of trains is expedited by 22 BLOCK SIGNAL OPERATION. having the switches operated from the block stations or cabins by the signal-men. The cost of the appliances for doing this is but little greater than that of good switchstands, while the cost of maintenance is much less in the former case than in the latter. Even if the block system is not axlopted for the government of the train service on the open line, it may be introduced to advantage at such isolated points of exceptional danger as those noted above. The fixed out-door signals used in blocking consist of home signals, advance (or starting) signals, and distant signals. They are preferably of the semaphore type, but other forms are often used, especially in automatic blocking. The semaphore signal was introduced on railroads about 1841, in England, by Mr. C. H. Gregory. Numerous other forms of fixed signals were used before its introduction and are still being used, but the semaphore is fast superseding all the others, and will undoubtedly become practically the only form in use. As appUed to railway signalling it consists of a vertical post from 3 to 40 feet in height, car- rying a movable arm pivoted near the top of the post This arm is usually capa- ble of being moved through an arc of about 70 degrees, but sometimes moves as much as 90 degrees. I [c]| |: ml I I tvn in O Wmmt Bounri Admmncm mnd C Wmwt Bound Dntunt len '^'snd O, t0 mdmit of thm Uso ofM. ompmrmf f^sf r e»oh Sfgnm/. ^ ^ % SIGNALLING AND TRACK. I THE BLOCK SIGNAL. 23 The semaphore is a signal of position only, in the case of home or advance signals, and of poaition and shape in the case of distant signals. At night, position is indicated by the color of a light placed above the semaphore arm and working in connection therewith. A semaphore home or advance signal will have one of two positions — horizon- tal or inclined. The horizontal position signifies " danger," or " stop " (block not clear), and is indicated at night by a red light. The inclined position (about 70^ below the horizon) signifies " safety," or " go ahead " (block clear), and is indicated at night by a white light. A semaphore distant signal is distinguished by its forked outer end, and will have one of two positions — horizontal or inclined. The horizontal position signifies " caution," or " go under control," and is indicated at night by a green light. The inclined position (about 70° below the horizon) signifies " safety," and is indicated at night by a white light. It is merely, however, an indication of the position of the home signal, to faciUtate the operation of a fast train service. Thus the hori- zontal position signifies that the home signal is at " danger," and the train must therefore go under caution and be ready to stop at the home signal if the latter has 24 BLOCK SIGNAL OPERATION. not in the meantime been lowered to indicate '' safety.'* On the other hand, the in- clined position cf the arm of the distant signal signifies that the arm of the home signal is also lowered. The distant signal i^ therefore only a preUminary signal to notify an engine-man of the condition of the block before he actually reaches that block, the block itself commencing at the home signaL In automatic blocking the signals are, as a rule, either of the " banner " or of the '' banjo," or disk type, except that in the electro-pneumatic system, signals of the semaphore type are used. The banner signal is usually circular, with slat openings to relieve it from wind pressuie. It rotates a quarter-circle. In the Union system " danger " is indicated by day by a full face view of the banner, and " safety " by an edge view of the banner, or by a full view of a banner of a diflFer- ent form. At night the different views of the banner are indicated by different colors from a light surmounting the banner. Signals of the disk pattern are enclosed in a case. This case has a white frosted glass in the back which is exposed through a glass covered front and forms the " clear " signal by day, when the disk is out of sight. When at " danger " the disk is displayed through the glass-covered front. In the Hall system the signals THE BLOCK 8I0NAL. 25 are indicated at night by alight showing through a small opening in the front of the case just above the largo opening. When the signal is at " danger " the small opening is covered by a red lens, which is actuated by the same mechanism that actuates the disk signal ; when at " clear " the light is white. The home signal is placed at the entrance to the block. At stations where there are cross-overs or sidings it should be so placed that trains can at all times run quite up to it without fouling any of the switches. In locating the homo signal on single track lines care must be taken that the blocks are not made to overlap. In other words, khe home signal governing the entrance to a block for trains running in one direction must be so placed that a train can go to it without encroaching on the block for trains running in the oppo- site direction. This should be the arrangement of the home signals at every single track block station, whether there is a passing siding there or not. The rule that a train leaving a block station has a right to proceed quite up to the home signal of the block station in advance should always govern in the locating of home sig- nals. Or, as a general proposition, it may be said of home signals for single track blocking, that they must be so located that two trains moving in opposite directions 26 BLOCK SIGNAL OPERATION. toward a common point can be stopped at that point clear of each other, by those signals. VThe advance signal is intended to hold a train which has been permitted to enlR* a short distance into a block fidready obstructed. It should be placed, when practicable, a maximum train length ahead of the home signal with which it operates. Generally speaking, an advance signal may be considered as dividing a block into two smaller blocks — one extending from the home signal to the advance signal, and the other from the advance signal to the home signal of the next block in advance. Distant signals indicate the position of home signals. They should be placed, when practicable, not less than 2,000 feet (more if possible) in the rear of the home signals with which they operate. While it is desirable to place the distant signal at least 2,000 feet from the home signal that it applies to, and the advance signal a maximum train length ahead of the home signal, this should not be done at the expense of having the dis- tant and advance signals out of the signal-man's sight, except where absolutely necessary, as for iustance, on heavy down-grades. THE BLOCK SIGNAL. 27 The normal position of block signals is '* danger " (" caution " in the case of distant signals;, except in '' normal safety '* automatic blocking. The signals are placed at "danger" immediately after the passage of a train, and in American practice are left so until permission is received from the block station in advance to let another train proceed under " safety," or as long as there is an obstruction of any kind in the block. In the "normal safety" automatic systems (with semaphore or disk signals), the signal for each block is cleared, or returns to " safety " as soon as the train has passed out of the block. In the " normal danger" automatic s}8 tems, the signal is only cleared in front of an approaching train (supposing ine block to be unoccupied). Trains may run up to, but not beyond, home or advance signals at "danger." They must not proceed until the clear signal or proper authority to pass the " danger " signal is given. When a distant signal is at " caution" trains may pass it under control, prepared to stop at the home signal. Home, advance and distant signals at " safety " may be passed without reducing schedule speed. A train that is to be held at an advance signal must first be brought to a stop 28 BLOCK SIGNAL OPERATION. at the home Eognal. It may then be allowed to proceed, under control, to the advance signal. The clearing of a home signal, in any case, gives authority to proceed to the advance signal only. To avoid the necessity of placing the home signal at " clear " for a train that is to be held at the advance signal, an auxiliary signal may be used. This is known as a '^ calling on " signal, and is a short sema- phore blade fixed upon the home signal post below the home signal blade. When in the '* safety " position this signal gives a train authority to pass the home signal at " danger " and proceed under control to the advance signal. Except in automatic blocking the signals are operated from the towers by means of levers resembling the reverse lever of a locomotive which are connected with the signals by wii'es or pipe. K wire is used there should be two lines for each signal, one for pulling it to " danger," and the other for pulling it to " safety." To ensure the signal being set at *' danger" in the event of the breakage of the wires the blade should be provided with a counterweight. Usually there is a lever for each signal, but in some instances, as at an inter- locked point, one lever may be used to operate several signals, by means of a device THE BLOCK SIGNAL. 29 known as a '' selector." The selector connects the signal lever with a particular signal of a series, the one so connected depending upon the position of the switch and the movement governed by the signal. The levers must be so interlocked that the home and advance signals require to be placed at '^ clear" before the distant signal can be so placed. This inter- locking is accomplished by means of locking bars attached to and operated by the signal levers. The locking machine consists of a frame canying the necessary locking bars, placed in front of or below the levers. Signal wires that are over 1,000 feet in length are often provided with somo device for automatically adjusting the effects of expansion and contraction due to changes in temperature, and the stretching of the wire caused by wear. The blades and lights of all the signals should be visible from the tower. Where the front lights cannot be seen, the lamps should be fitted with back lights, the latter being as small as practicable, having regard to efficiency. Where the front lights can be seen from the tower, back-lights shoald not be provided. If a signal is so situated as to be out of the view of the signal-man, a '' signal repeater " and a " light commutator " working in connection with the signal, may be placed in the 30 BLOCK SIGNAL OPERATION. tower to indicAte respectively the position of the sigaal, and whether the light is '' in " or " out." The signal repeater is an electricallj operated instrument hav- ing a miniature signal arm, and when the outdoor signal is lowered this miniature arm is at an angle of 46^ below the horizontal, the armature then assuming a ver- tical position by gravity. When the outdoor or line signal is set at *^ danger " the action of a commutator fixed on the line signal-arm forms a circuit which causes the miniature arm to assume a horizontal position. Separate signals are provided for trains in each direction. Where semaphore arms governing trains in opposite directions are mounted on the same post, the one on the right hand side of the post as viewed from an approaching train governs that train. Each track must have its own block signals. Where trains proceed in the same direction on different tracks, the signals relating to these tracks are generally placed on the same post, or, as shown on page 170, on a bridge spanning the tracks. In the former case the post supports a cantilever bracket carrying short posts upon which are mounted the signals, the post carrying the main track signal being higher than the others, and nearest the main track. An arrangement of signals for trains THE BLOCK SIGNAL. 31 in the same direction on different tracks that is simpler, is to have the signal governing the main track movement on a high post bj itself and all others on low posts. As all movements from and on aide tracks are made at comparatively slow speed, the position of low signals may be readily observed by those interested. Then only the signals governing the through main track movement will be con- spicuously visible from a train approaching on the main track. This method of signalling is especially convenient for high speed movements, as where there is but one set of conspicuous signals, and that governing the through or high speed movement only, there is no reason for doubt in the mind of the engine-man of an approaching through train as to which signals govern hiuL Where blocks are short, as in yards, it may be necessary to place the distant signal' of a station on the post of the home or advance signal of the station in the rear. When a distant signal so placed is at '^ caution " the signal-man at the rear station must keep his distant, home and advance signals (or such as are pro- vided) against any approaching train until the train is brought to a stop. If there is no obstruction at his station, and he has received "block clear" from the station in advance, he may then lower his signals for the train to go forward, but this does not 32 BLOCK SIGNAL OPERATION. relieve the engine-man from keeping the train under control in approaching the home signal of the block ahead. As the color of the blade has nothing to do with semaphore signal indication — position and shape of blade only governing in this matter — the color best adapted to local conditions may be used. On many lines home and advance signal blades are painted red, with a broad white stripe across near the outer end, and distant signals are painted green with a similar white stripe. On other lines orange has been adopted as the color for distant signals. Local characteristics, such as the color of the background and atmospheric conditions may be allowed to govern, al- though for many reasons a uniform standard is desirable. The selection of any particular colors for signal lights, as white for " safety " or "go ahead," and red for " danger " or " stop," is somewhat arbitrary. Any colors may, with propriety, be used. In fact, on some of the leading English lines, green has recently been adopted as a " safety " signal, the use of red as a " danger " signal being continued. Green, instead of white, is used for " safety " to prevent the mistaking of a white light in the neighborhood of a block signal for a " clear " sig- nal, in tho event of the signal light being out ; another purpose is to prevent the THE BLOCK SIGNAL. 33 signal light from showing clear, when tbe reverse is intended, in the case of the glass lens being broken. On American lines white is commonly used to denote " safety," " go ahead ; " red, '' danger," " stop ; " and green '' go ahead cautiously to the next signal." The Joint Committee on Interlocking and Block Signals, of the American Bailway Asso- ciation submitted this, at the meeting of the Association, in April, 1895, as the Com- mittee's recommendation relative to the colors of night signals : " The Committee does not at this time deem it wise to recommend abandoning * white ' for a night signal, — as, — first, three indications are necessary in many cases, and second, no entirely satisfactory single color has been found for a third indication. The Committee approves, however, the use of ' red * for * danger,' * stop ; ' and * green ' for * clear,' * proceed ' ; as good signal practice." An electric slot, or reverser, for automatically returning the home and advance signals to '' danger " after a train has passed them, is of great advantage in the manfual system, as by it a train protects itself efifectually against following trains. This apparatus is actilated by a track circuit, as described on page 165. Another useful appliance is the ''mechanical slot," a device by which a 34 BLOCK SIGNAL OPERATION. distant signal is put under the control of the signal-men at any number of nearby points — often a desirable feature. This device avoids the necessity of a multipli- cation of distant signals. With it the consent of all the signal-men concerned is required to place the signal at ^' clear," although any one of them can place it at "danger." CHAPTER IV. THE SIGNAL LAMPS. « Signal lamps should give sufficient divergence of the rays for the light to show clearly around an open curve, if located thereat. Good drainage and good ventila- tion must be provided for in the lamps, and since much depends upon the proper working of these lamps, every care must be taken to keep them in good condition. The greatest trouble arises from failure to clean the lamp cups weU and to properly adjust the flame at the start. It is of the utmost importance to have a low flame at first, as this prevents the overflowing of the oil from the wick feeding too freely. Overflowing oil is apt to take fire and destroy the lamp. If the flame is too high, the lamp will smoke badly, thus choking the ventilator holes. If the flame is too low, the wick is apt to become crusted, which prevents free burning and keeps the 36 BLOOK SIGNAL OPERATION. heat below the cmst. As a consequence the thin brass of the bnmer becomes so hot as to generate a gas in the lamp cup, often causing an explosion. The follow- ing are some of the points that should be observed in the care of a lamp : 1. Fill the oil cup, trim the wick and clean the lamp daily. 2. The wick should fit neatly in the burner. 3. The wick may be best trimmed by carefully scraping oflf the burnt portion. It should not be trimmed by cutting. 4. When the wick becomes gummy or obstructed and does not draw oil freely, reverse the wick end for end. 5. Be careful to have a low flame at first, and to regulate it carefully about ten minutes after lighting. 6. If the burner giv^s a ra^ed flame it probably needs cleaning. If cleaning does not correct the trouble a new burner should be put in. 7. TVhen the lamp is not lighted, turn the wick down so that its top is in the tube, to prevent overflowing of oil. 8. In cleaning the lamp, remove the cap at the top, and clean out all soot which may have collected in the ventilator, but be sure to replace the cap. THE SIGNAL LAMPS. 37 9. Keep the lenses perfectly clean inside and out. If the smoke and dirt cannot be removed from them otherwise, use sand and water. 10. Before lighting be careful to wipe off all oil from the inside of the lamp, especially from the cup. Electric light, where ayailable, gives the best satisfaction in signalling, and these lamps, being free from grease, smoke, etc., require much less attention than others. The Pintsch gas system could be used to advantage where there are a number of signals in one neighborhood, as in yards and at interlocked points. The " light commutator" is an instrument to be attached to the signal lamp und connected by an electric circuit with a repeating instrument in the tower, and its use is desirable if the light is so situated that it cannot be seen from the tower. The contraction of certain metal rods in the " light " instrument, caused by the reduction of temperature when the light goes out, breaks the circuit, releasing the armature of the magnet in the tower instrument. This causes a bell to ring, and also gives visual notice by showing the word '^ out " on the indicator of the tower instrument. CHAPTER Y. THE BLOCK TOWER. The block tower, used only in systems of blocking reqniring men to operate the signals, is generally a two-story building, with the office located in the second story, so as to secure from it a good view of the line and of passing trains. The tower is of a size depending on the number of signal levers at the station. A good view for the signal-man is essential, it often being necessary for him to note the movements of two trains passing tbe block station at the same time. The batteries for working the bell wire and for working the ordinary telegraph wire should be kept in the tower where they will not freeze. The battery boxes may be located on the lower floor where they can be attended to and cleaned without littering the office. 40 BLOCK SIGNAL OPERATION. Following are the Western Union Telegraph Co.*s instractions relative to attaching office wires : '' Cross arm fixtures should be attached to office buildings with bolts passing through the wall instead of door or window casing wherever it is practicable to fasten them in this way. Screws should never be used for fastening fixtures to buildings, as thej are liable to pull out when subjected to a heavy strain. ** The full sized line wires should be carried to the inside of the building from the standard glass and pin insulators on a cross arm attached to the wall with iron fixtures iu such a manner that the wires will have an upward direction from the insulators to the point where they enter the building, to prevent rain and moisture from following them to the wall. Where the wires run into the building in exposed places, they should be covered with a sloping roof board of sufficient width to perfectly protect them from rain and snow, and should be insulated with rubber tubing where they pass through walls and partitions, using tubing of sufficient length to go entirely through the wall from outside to inside of the building. '* Wliere telegraph offices are located in railway stations or similar long build* ings, the wires should enter such offices at the vrindow or other opening nearest THE BLOCK TO WEH. 41 the switchboard, and should be so stning that they can be plainly seen and easily inspected at all times. *' At railroad crossings all wires must be kept at a height of not less than twenty-five feet above the rails and at public and private highway crossings not less than eighteen feet above the roadway. " Porcelain insulators and knobs must not be used outside of buildings. Rubber hook insulators must not be used outside of buildings, except in places where they are completely protected from rain, snow or moisture and where it is impracticable to use the standard glass insulation. " In the construction, reconstruction and general repairs of lines, all splices must be soldered. '' All connections between copper and iron wires must be soldered. " The wires inside of a building should be insulated on wooden cleats, and kept as far apart and as far from the ground as possible. The use of staples for attaching office wires is forbidden. "All connections in main battery wires must be soldered and the wires insulated. 42 BLOCK SIGNAL OPERATION. " Permanent terminal ground wires should be composed of Number 8 copper wire, and they should be soldered to the main gas or water pipes, where prac- ticable." The windows in front of the lamps of the tower should be screened to prevent the lights from being mistaken for signals. The station number or call should be painted on the front and sides of the building, and may also be cut on a window glass on each side of the tower, so as to be conspicuous to approaching trains. The stove, on accoimt of its dust and dirt, should be located on the ground floor, and the office heated by a register or dram. The drum will perhaps give the better result CHAPTER VI. SIGNAL BELLS. In manual and controlled blocking the signalling of block stations with each other is usually done through electric bells. The bells governing each block are connected by a separate wire, thus : A B C D E F The bell apparatus of a block station consists of a battery, and, for each block, an electric bell of distinctive tone and a double-point strap-key for working the bell at the opposite end of the block. The Leclanche battery, if properly con- structed, gives excellent satisfaction in bell signalling. It is easy to maintain, usually lasting without attention for nine months. The single stroke bell gives the best results in code signalling. Vibratory bells may be used, but they are nut 44 BLOCK SIGNAL OPERATION. so satisfactory, the tendency of signal-men being to work the bells rapidly, which causes the strokes of the vibratory bells to run together and be unintelligible. The bells should not be used for other purposes than signalling trains, except when they are used by inspectors or linemen in making tests or repairs. A code for carrying on private conversation might be misunderstood and lead to an error in train signalling. The general causes of failures of electric bells are imperfect contact, faulty ad- justment, and defective insulation. Wooden bases for bells may also cause trouble, by warping. The magnets, armatures and other working parts should be covered to protect them from dust, dampness, etc., and care taken to keep all parts free from dust, dirt, grease and rust. The bells should not be worked too quickly, but esM^h movement of the key should be made sharply and distinctly, so as to give a clear and distinct stroke on the bell for each touch on the key. Good wiring is essential to perfect working of the bells. The bell hammer must also be adjusted to move within a carefully defined space, as slight variations are apt to cause an unsatisfactory action of the hammer. CHAPTER VII. THE BLOCK RECORD. The prompt handling of trains, in manual and controlled blocking, depends largely upon keeping a complete "block record" of the bell signals for each train movement. To this end the record should show the time " block clear " was given, the train number (or at least the engine number of the train), the time the train was rung in from the rear block station, the time the train arrived at the block station keeping the record, the time of departure and when " train clear " was given to the block station in the rear, and the time " train clear '* was given by the station in advance. In single track blocking the record. should show the time each bell signal relative to " head-to-head " movements was received. Under " remarks " should be noted the number of each train taking a siding or back- 46 BLOCK SIGNAL OPERATION. ingover onto the opposite track, with the time the train took the siding or opposite track, and the trme it returned to its own track. Any information relating to acci- dents to trains, obstractions in the block, unusual work done by track men, and the times at which the lamps were lighted and extinguished should be noted. In fact, the record should contain an outline history of the day's work at the sta- tion. Obviously that part of the record relating to the movement of trains is the most important, and signal-men must make those entries at once. Each signal- man when going oH. duty should sign his name on the block record, and enter upon the record the time during which he was on duty. The block record should begin at midnight, a separate page or sheet being used for each day's business. All block records should be sent to the superintendent's office for filing. The following is a copy of the form of block record used on the Erie Bailroad : ERIE RAILROAD CO. BLOCK EEOORD. 47 Operates on Duty -M. to M. M, to M. V Signal Office,. -M. to M. .189 EASTWABD. WESTWARD. rROM ABBITBD D.PARTED 1 REMABKS Tiunv BUMO IN FBOM DKPAHTJU) AND OLKAB oiyxN CLRAB FBOM REHABKfl TBAIM OIVUI ABHITBD Note.— These reoords moit be kept complete and filed vmj each day for refex«noe. Use Ink. CHAPTER VIII. TRAIN ORDEES AT BLOCK STATIONS. Rule 524 (B) of the standard code of train roles, American Railway Associa- ton, says in substance : While a red train order signal is displayed, aU trains must come to afvU stop, and any train thus stopped may pass the red signal after receiv- ing an order addressed to such train, or a dearanoe card on a specified form staling over the operator's signature that he has no orders for it. When block signals are in nse, this rule must not be construed as giving a train authority to pass a block sig- nal, even after the train has received train orders or a train-order clearance card. When it is necessary to place a train order at a block station, in the absence of a fixed train order signal a red flag by day and a red light by night, indicating ** train order," must be displayed from the side of the block station facing the train TRAIN ORDERS AT BLOCK STATIONS. 49 for which the order is held. After the order has been delivered, the signal-man and those in charge of the train must be governed wholly by the block rules in having the train go forward. If a train arrives at the block station ahead of the train for which orders are held, to the train ahead must be given a written notice in the form of a train order clearance card, that the train order signal is displayed for a speci- fied following train. This notice pertains only to the train order signal and gives no authority whatever to pass the block signal, which may only be passed as pro- vided in the block rules. During the time a train order is held at a block station the block signal must be kept at ** danger," except to allow a train to pass accord- ing to block rules, when such train has received authority to pass the train order signal. CHAPTER IX. BLOCKING AT EAILROAD CROSSINGS AND JUNCTIONa The principle of absolute blocking at junctions, or at crossings at grade is that all the blocks intersecting at a junction or crossing frog shall be operated as one block. At a single track junction or crossing, when a train is approaching from any direction, or fouling the frog, all other approaching trains must be held back until this train has cleared the frog. At a double track junction or crossing, when a train is approaching, or is foul- ing the frog, other trains must not be allowed to approach the junction or crossing (except on the parallel track of the same line), until this train has cleared the frog. Junctions and crossings should be provided with the regular block signals, BLOCKING AT BAILROAD CROSSINGS AND JUNCTIONS. 51 and also with interlocked switch signals, and with derail switches. The latter are opened when the signals with which they are connected are set at " danger/' so that a train running past a signal at '' danger " will be turned off the track before it can meet a train on another track at the fouling point. Where the track is level tne derail switch should be placed not less than 500 feet from the fouling point On a grade descending toward the junction or crossing, the derail should be placed far enough awav to give the same degree of safety that it would on a level track at a dititance of 500 feet. The block signals, switches and switch-signals should be so interlocked that a clear block signal cannot be given when there is an intervening switch set for a. different movement. In other words, the switches must be set to give a clear route or track before the signal can be set to indicate *' safety " for that route. At railroad crossings and junctions distant signals should be provided, placed when possible not less than 2000 feet from the fouling point, and on descending grades, placed far enough away to give the same degree of safety that they would give on the level at a distance of 2000 feet. The rules for operating the block system are the same at railroad crossings 52 BLOCK SIGNAL OPERATION. and jonctions as at other points. In addition to the block roleSy special instruc- tions in regard to the interlocking switch signals, and covering local conditions, should be issued for each interlocked station. These instructions should include the location and use of each signal and derail switch, and, where more than one signal blade is displayed from a post, the instructions should state, specificallj, the route each blade refers to. Signals controlling " back up " movements— or move- ments opposite to the current of traffic on main tracks — should be clearly described, and the movements as well as the territory controlled by each signal should be stated. BLOGKINO AT RAILBOAD CR088IN0S AND JUNCTIONS. 53 The following diagrams show some of the principal arrangements of block signals at railroad crossings and junctions : D ^ SoufhBffumfJ i? South Bound |S IkrattSmfcfi.. South Bound ^'\ HomeStqnal^ rNorfhBcwid Ad^anctSignaL 4 \i\ ^NorHiBound ^r^HomoSignal. '•North Bound DerailSwftdi. ^Norfti Bound r" Distant Signed <3 ^ v/5 I South Bound \ Advance S^nal ^ BLOCKINQ AT A SINGLE TBACK BAILBOAD caossiNQ. I Oktant Signed -^ Dmn'fSwfMt ra c I c >\ V>^tt Bqwnd Tnatk Ea»t BOuna Track II |l Advance Stgnat ^ I i§ 1 B dj-w^ 2 t I SI I V'DttailSwitdi. -& BLOCKma AT A DOUBLU TBAOK BAILBOAD CBOSSIMQ. BLOCK aWNAL OPERATION. ^' \ « Woh BLOOEIKa AT A SIRai^ Aim DOUBLB TKAOX JUKOTTOK. BLOCKING AT BAJLBOAD CB088INQ8 AND JUNCTIONS. 65 i EQ»t^ Bound Easfoound IHstont. BLOCKING AT A DOUBLE TBAOX JUROHOV. BLOCK SIGNAL OPEBATIOtT. r fs Uou ii I ASD IX>CBIia TSAOX InKOTIOH. BLOCKING AT RAILROAD CROSSINGS AND JUNCTIONS. 65 BLOOKINO AT A DOUBLE TBAOK JUROTIOir. BLOCK SIONAL OPERATION. »s^layed, the conductor shall personally direct the engine-man to proceed, after the proper signal is displayed. 10. The conductor of a train taking siding (to be met or passed by other trains) must immediately report to the signal-man at the tower at the station at which ho takes siding as soon as his entire train is clear of the main track. n . When it is necessary for a train to cross over on to the opposite track, the conductor, before crr)Hsii]g, shall notify the signal-man at the block station nearest MANUAL BLOCKING. 141 the cross-over to be used. The signal-man shall then notify the signal-man at the next block station in the direction in which the train is moving, and the train shall not cross over until the conductor is notified that the signal-man at the block station in advance has been notified, and a flagman sent out. * * * When the signal-man in the advance station is notified, he shall stop any trsiin approaching on the opposite track, and notify the conductor and engine-man in writing that the train has crossed over. He may then allow it to proceed under a green signal. If a train is in the block on the track to which the train is to cross, the signal-man shall not permit this train to cross over until the other has arrived at his station. When a train pulls or backs out of a siding or crosses back to its own track, be- fore doing so the conductor shall notify the signal-man at the block station nearest the.switches to be used. The signal-man shall then notify the signalrman at the next block station in the rear, and the train shall not pull or back out or cross over until the conductor is notified that the signal-man has been advised. When the signal- man in the rear block has been so notified, he shall stop any train approaching on the track obstructed, and hold it until the block is clear. If a train is in the block on the track to which the train is to pull or back out or cross back on, the signal- 142 BLOCK SIGNAL OPERATION, iDan shall not permit the train to pull or back out or cross over until the train has arrived at his station. 12. At starting and junction points a train shall not go on to the main track until a signal to proceed has been given, and this shall not be given until the train has been protected on the track it is to enter upon or cross ; this must be done by notice to the block stations in the proper directions and by use of signals as required in the rules, or by fixed signals. 13. When from any cause it is necessary to couple two or more trains together to be run as one, they shall not be separated under any circumstance until the train arrives at a block station. K they are then separated, each train shall be governed thereafter as a single train. 14. On a double track, if one is obstructed, the same advance or block signals shall govern trains using the left-hand track that would govern if they were on the right-hand track. 15. Every train, while running, must display two green flags by day and two green lights by night, one on each side of the rear of the train, as markers, to indicate to the signal man that the entire train has passed the station. MANUAL BLOCKING. 143 16. When a train passing a block station has no markers, the signal-man shall notify the signal-man at the block station on each side of him in the prescribed form, and the signal-man at the station in advance shall stop the train, and ascer^ tain why markers are not displayed. The signal-man at the rear station shall con- sider the block obstructed until notified in the prescribed form that it is clear. 17. Signal-men should closely observe each train as it passes their station, and if anything about it is noticed wrong, such as a swinging car door, brake beam, or anything else hanging, which looks to be dangerous, they shall notify the block station in advance in the prescribed form. The signal-man in the advance station shall stop the train and notify train-men of the dangerous condition of their train* 18. An operator having orders for a train shall display a red signal in addition to the block signal. 19. In displaying green signals under these rules, the signal-men shall use a green flag by day or green lamp by night, and shall hold the signal with the hind outside of the signal-house window and in full view of trainmen. When the signal is not in use it must be kept out of sight of approaching trains. If the blocks in both directions are not clear or are obstructed when two or 144 BLOCK SIGNAL OPERATION. more trains are approaching a block station at about the same time, and the signal-man has occasion to give the green signal to only one of them, but cannot do it without the other trainmen seeing the green signal, they shall all be stopped and the trainmen of the train that is to proceed under the green signal properly notified. In displaying red signals for train orders at the block stations, a red flag by day or red lamp by night shall be used outside of the signal-house window in full view of trainmen, except where fixed train-order signals are erected. Flags must be kept clean, and must be renewed when their color becomes indistinct. 20. When trains are delayed, from any cause, at stations, or in a block, a flag- man shall be sent back to protect the train, as though it were not protected by block signals. 21. A train shall not pass a block station when red is displayed, except under the conditions herein provided. 22. Night signals shaU be displayed from, one hour before sunset until one MANUAL BLOCKING. 145 hour after Bunrise, and when, bj reason of storms, fog, or other causes, the day signals cannot be clearly seen. Operators shall promptly report to the train dispatcher the condition of the weather in case of fog or storm. 23. The rules governing the use of block signals do not relieve trainmen from observing all other rules relating to the protection of trains. 24. Signal-men shall promptly report to the next block station, in ea>ch direction, the movement of trains passing their stations by means of the prescribed code. 25. Signal-men shall be governed by the following bell code : BELL CODE. 1. Acknowledgment of any signal except as herein provided. 2. All right? Yes. 3. Unlock my lever (Sykes system). Answer by plunge, 6 or 3-L Is block clear? Answer by 2 or 5. 4. Train has entered block. 5. Block not clear. Or, block obstructed. 146 BLOCK SIGNAL OPERATION. 6. Is there a train coming to me ? 2-1. No. 2-4. Has train cleared? Answer by 4-2 or 5. 3-1. Have plunged (Sykes system). If you are not unlocked, allow train to proceed under green. Bepeat 3-1 to sender. 3-3. Train is on siding clear of main track. Allow train to come in block under clear signal. 3-3-3. Train to you broken in two. Answer by repeating 3-3-3 to sender. 2-3-2. Signal just received, not understood. Please repeat. 4-2. Train has cleared. 4-4. Train is going on side track. 2-2-2. Error signal. Bepeat to sender. 6-4. Testing signals. Bepeat to sender. 9. Stop train. Has no markers. 3-2. Train from you passed without markers. 5-5. Train has crossed over on to opposite track. Bepeat to sender. 2-5. Stop and examine train. MANUAL BLOGKINO. U7 3-5. Train is returning to its own track. 4-1. Train has left preceding passing track (to be used only on single track). RULES FOB WOBEINa BELL CODE. No. i. 1. Acknowledgment for any signal except as herein provided. No. ii. 2. All right. Tes. No. iii. 3. Unlock my lever (Sykes system). Is block clear ? Give to sig- nal-man in advance block station as soon as you receive 4 from signal-man in rear block station. No. iv. 4. Train has entered block. Give to signal-man in advance station as soon as first portion of train passes the signal governing that block. No. V. 5, Block not clear. This signal will also be used to notify signal-men in both directions in case of accident or obstructions of any kind. Signal-men receiving this signal will hold all trains until notified that the block is clear. (See page 151). No. vi. 6. Is there a train coming to me 7 No. vii. 2-1. No. 148 BLOCK SIGNAL OPERATION. No. viii. 2-4. (Has train cleared yet ?) To be given when you have not re- ceived clear for a train that has entered the block which you think has had time to clear. In case the reply is 4-2, give 3 and receive 2, or plunge before allowing train to proceed. No. ix. 3-1. (Have plunged. [Sykes system]. If you are not imlocked, allow train to proceed under green), announcing by 4. This must be given only when you find by plunging you do not release the signal in the rear, and are certain that the last train that you plunged for has passed. Bepeat 3-1 to sender. No. X. 3-3. (Train is on siding clear of main tracks. Allow train to come under clear signal). To be given to signal-man in rear when a train has taken sid- ing and you are positive it is clear of main tracks, and switches closed. No. xi. 3-3-3. (Train to you broken in two). Signal-men receiving this signal will use every eflfort to notify trainmen that they are broken in two, and to prevent the detached portions from coming together. If block ahead is not clear, allow the head end to go on green signal, giving them an additional signal * * * * that they are broken in two. No. xii. 4-2. (Train has cleared). Qive to signal-man in rear station as MANUAL BLOCKING. 149 soon as the train bearing markers has cleared and your signal is thrown to danger in real* of train. No. xiii. 4r4. (Train is going on side track.) No. xiv. 2-2-2. (Error signal.) To be given when yon have given a signal in error, and must be repeated to sender. No. XV. 6-4. (Testing signal.) Must be repeated to sender until acknowl- edged by 1. No. xvi. 9. (Stop train and notify them of absence of rear signals.) No. zvii. 3-2. (Train from you passed without markers.) To be given to station in rear, who must hold following train until clear has been given. No. xviii. 6-5. (Train has crossed, or is going to cross over on opposite track.) This signal must be given to signal-man in direction in which the train is going to cross over, who will stop any train approachii^ in opposite direction, and notify the conductor and engine-man in writing that a train has crossed over. He may then allow it to proceed under green (see page 162).''^ • When tnina croas OTor at Interlockiiig points and are protected by distant and homti iiignalfl. this rule will not apply. 150 BLOCK SIGNAL OPERATION. No. xix. 2-5. (Stop and examine train.) Signal-men receiving thid signal shall stop the train and notify trainmen. When signal-men are operators, they shall notify the advance station by telegraph what they noticed wrong about the train. No. XX. 3-5. Train is returning to its own track after having backed over or is taking main track from siding. This signal to be given signal-man in the direc- tion from which trains are approaching, who will hold any train until notified that track is clear for approaching trains by 4-2. If the train which is taking main track from siding will foul both main tracks, this signal will be given to signal-men in both directions. Signal-men in both directions will hold trains as provided above* No. xxi. 4-1. (Train has left preceding passing track.) Signal-man at first advance block from a passing siding receiving signal 4 will give the signal 4-1 to signal-man in advance block, to be repeated through intermediate blocks to signal- man at passing siding in advance. Signal-man at passing siding receiving the sig- * When trains are returning to their own tracks at interlocking points and are protected by distant and home signals, this rale will not apply. MANUAL BLOCKING. 151 nal, viz.: 4-1, will not allow any train to leave his station until the train or trains for which he has received this signal have arrived at his station. Na zxii. Operators must bear in mind that in order to give distinct signals the key must be pressed down firmly ; short, quick taps on the key give imperfect signals. No. xsdii. Care must be taken to keep the contact points of the key clean. Dirty points make bad connections, and are Uable to prevent the ringing of the belL SYEES APPABiLTUS. No. xdv. Never plunge unless asked to do so, and also never ask to be released until train has been rung to you.'* Signal-men must be prepared to act promptly upon receipt of bell signal 5, the *' obstruction danger signal," (see Erie BaUroad Bules, pagel47), as upon the prompt handling of this signal may depend the safety of a train. If this signal is received after the out-door signals have been placed at ^' safety " for an approaching train, they must be returned to *' danger " as quickly as possible. Should a train be pass- 152 BLOCK SIGNAL OPERATION. ing at the time every effort must be made to stop it. Auxiliary danger signals con- sisting of a red flag for use by day and a red light by night, and at least six torpe- does (detonators), all in condition for immediate use, must be kept at each block station. One torpedo must be placed on the obstructed track, on the engine-man's side, as soon as the signal 5 is received, and must not be removed imtil the signal is cancelled. When a signal-man receives bell signal 5-5 he may allow a train to proceed cautiously to the block station from which the signal is received, after notifying the conductor and engine-man in writing that a train has crossed over to their track. A train must not pass to the opposite track until the bell signal 5-5 has been sent and acknowledged as prescribed, nor until the arrival of any train that may be ap- proaching on that track. A train that is occupying the opposite track should be within cover of the home signal, so that an approaching train can run up to the sig- nal. A safe rule for the engine-man of an approaching train to follow, in making this move, is to run under such control as to be able to stop at the distant signal, if necessary. On heavy down grades the 5-5 signal should not be used. MANUAL BLOCKING. 163 MOZIER SYSTEM. On the New York, Pennsylvania & Ohio line of the Erie Bailroad (Ohio Divis- ion), the Mozier system of blocking is used This system differs from the ordinary manual blocking in that the passage of a train into a block is controlled by the train dispatcher, no tram being allowed to enter a block without his permission. When a train enters a block the dispatcher is notified of the fact by wire, and he then directs the signal-man at the station in advance of the train what signal to display to the train on its arrival there. The out-door signals used in this system are of the semaphore type, and can be placed in three positions — the ordinary " clear '* and '' danger " positions, and a '' cautionary " position in which the signal inclines about 45^ above the horizontal. A METHOD OF SINGLE TRACK BLOCKING. While single track blocking must govern both the non-meeting and the non- following movements, its main object is to control the non-meeting (head-to-head) 154 BLOCK SIGNAL OPERATION. movements, which are the more important. To accomplish this it should provide for holding a train at a passing siding while another train moving in the opposite direction is approaching that point. There are two principles in single track blocking which should always be kept in mind. First, all meeting and passing points must be at block stations. Second, for the non-meeting movements that section of the line between the passing sidings must be operated as one blocks regardless of intermediate block stations. Where the distance between passing sidings is considerable it may be neces- sary to put in intermediate block stations for governing the non-following move- ments if the traffic is heavy. The necessary bell signalling from one passing point to another can be done expeditiously by means of a separate wire and beUs con* A B C D E F DIAGRAM NO. 1. necting these stations only. This is shown in the diagram No. 1. The passing sidings are at A and F, and there are intermediate block stations at B, C, D and MANUAL BLOCKING. 155 E. All the block stations are connected by wires, as shown by the shorter lines, while a separate wire connects the stations at the passing sidings, as shown by the longer line. This wire should be used in signalling for the non-meeting move- ments only, the bell wire from station to station being used for the non-follow- ing movements, as in double track blocking. The separate wire can be dispensed with, however, by repeating the A — P signals through the intermediate stations. When a train is to take the siding, the block station at the siding should be notified of the fact in advance, so that means may be taken to prevent delays to opposing trains. The train should communicate its intention to the block station in the rear of the passing siding by a pre-arranged whistle signal or by a written notice signed by the conductor. The signal-man, after ringing in the train (" train has entered block") to the signal-man at the siding, should impart to him the addi- tional information given by the train. The following additional bell notifications are required in this method : Hold all trains coming to me. (" Hold '* signaL) No train going to you. Cancel " hold " signaL 156 BLOCK SIGNAL OPERATION. Train to you from passing siding. Train from you clear. Train last rung in takes siding. The mode of operating head-to-head movements under this method is as fol- lows : Prior to starting a train from the passing siding at block station A, (see Diagram No. 2) the signal-man there calls the EOgnal-man at block station D, at the A B H B I DIAGBAM NO. 2. next passing siding ahead, by one stroke of the bell ('' attention "), which signal is acknowledged by D. A then gives to D the signal '^ Is there a train coming to me?'* If there is no train moving from D to A the signal "No train going to you " is given by D and acknowledged by A. A then signals to D, "Hold cdl trains coming to me." D acknowledges this signal and is governed by it until he receives MANUAL BLOCKING. 157 from A the signal '' Cancel hold signal." As soon as ihe head end of the train enters the block, A signals to D, " Train to you from passing siding/' which signal D acknowledges. The ''hold " signal should not be kept in force bj A when there is no train in the block, but should be cancelled as soon as the signal '' Train from you clear " is received from D for the last train sent by A. As soon as the train, with markers, has passed D, the signal " Train from you clear " must be given to A. It is suggested that separate ringing-in notifications be used for passenger and freight trains, as follows : Passenger train has entered block. Freight train has entered block. It is fair to presume that the ringing-in as such of passenger trains — on most lines the less frequent but always the more important movements — will naturally cause the signal-man to be especially on the alert for these trains. As a further precaution, each signal-man should, as soon as he has placed his signals in the " danger " position after the passage of a train, notify the signal-man at the station in advance that he has so placed his signals. If the signal-man in the advance station does not receive this notification promptly after receiving the 158 BLOCK SIGNAL OPERATION. signal '' train has entered block," it will be his duty to ask for it. This will necessitate the use of two more bell notifications, as foUows : My signals have been placed in the " danger *' position. Are your signals in the " danger " position? For single track blocking the '^ lap " siding seems to be the best arrangement for a passing siding. The lap siding is an arrangement of passing fcracks on a sin- gle track line, whereby double track is provided at meeting points, with the switches so arranged that trains moving in opposite directions cannot interfere with each other at the passing point, as shown in Diagram No. 3. For example, two trains are to pass each other and to be passed by a third train. Both of the two first mentioned trains take their respective sidings, one at A and the other at B, and wait until passed by the third train. Then, in proceeding, neither train obstructs the other, as the eastbound train moves to the right and the westbound train to the left in order to regain the main track, and turnouts for their respective sidings are separated by a short stretch of the main track. In operating lap sidings greater safety may be secured at head-to-head meeting points by making both trains take their respective sidings even when a third train is not included in the MANUAL BLOCKING. 159 moyement. This will prevent any misunderstanding at an irregular meeting point as to which train should take the siding, and will cause no serious delaj^ as, properly, trains always come to a fuU stop at meeting points. ll 1^ ^ ± « ^ is S-^ I J^VestBoundfasslnqSidinq ^•East BounilBasjingSidin + F^ Main Track- fill DIAGBAM NO. 3. LAP SIDINa. s I II B w -A train using a " lap " siding at a meeting point should enter the siding at the far end, and the train to be met, if it is to keep the main track, should be held 160 BLOCK SIGNAL OPERATION. at the home signal until the arrival of the other train on the siding. By this arrangement the two trains are kept a safe distance apart while the passing is being accomplished. Safety switches placed at the clearance point of the station ends of passing sidings and working in connection with the main track switches will form an additional safeguard against trains in opposite directions fouling at passing points. At meeting points on single track, when two trains are approaching in opposite directions, the home signal must be kept at " danger '' until both trains are brought to a full stop, and the signal must not be given to either train until the signal-man knows that the track is clear for the required movement. OPEEATING OUTLYING SWITCHES. The JfewTork, New Haven & Hartford Bailroad, on its New York Division, has the following instructions in regard to a train or an engine taking an outlying siding : " Engine-men of trains that are to take an outlying siding in any block will so notify the operator at the rear tower by six low, short, blasts of the whistle, given thus : . MANUAL BLOCKING. 161 '^ Tower-men receiving this signal must give 3-3 to the advance tower, which must be answered by repeating. '' A train or engine having taken an outlying siding, clear of the main line, and all switches being set and locked for the safe passage of trains on the main track, the conductor will give the following signal from the switch-house : 1-2-3 (6 beats, given thus : 1, short pause ; 2, short pause ; 3). " This signal must be repeated until it is answered by the same signal given from the tower in the rear. " When ready to leave siding the conductor will give the following signal : 3-4 (7 beats, given thus : 3, short pause ; 4.) '' This signal must be repeated from the tower before the switch is unlocked or main track obstructed. If the acknowledgment (3-4) is received, the train may leave the siding, but must be protscted by flagman while so doing. If signal 3-4 is answered by 5 beats of the bell, ic will signify that the block is not clear and train must remain on siding until the signal 3-4 is received from the tower. " In case of failure of the bell signals, the train on siding may cautiously follow a preceding train ten (10) minutes after its passage, provided it can clear the 162 BLOCK SIGNAL OPERATION, schedule time of all trains of superior rights at least ten (10) minutes, and that it is protected as required by the rules, before obstructing the main track and until it has passed the next tower. " Conductors must attend to signalling from switches in person and will be held responsible for the strict observance of the above rules. *' A tower-man receiving the signal 3-4 will first ascertain whether the block ahead is clear, and, if so, and there is no other train approaching having superior rights, he will give the signal 3-4 and allow the train on siding to proceed. If his signals have been unlocked for a foUowing train, or if there should be any other reason why the train should not leave the siding, the signal 5 should be given instead. When a tower-man has permitted a train to pass from an outlying siding to the main track, he must immediately announce it to the advance towerman and both must take all necessary precautions not to admit another train to the block until the train from the siding has passed the advance tower." CHAPTER XI. CONTBOLLED MANUAL BLOCKENG. In controlled manual blocking the manipulation of the out-door signals at the entrance to a block is controUed, electrically, by the signal-man at the block station in advance. In what is sometimes termed the auto-manual system there is at each block station a track circuit of at least two or three rail lengths, which is used in actuating an '^ electric slot " (see page 165), for automatically replacing the home signal to " danger " when the rear end of a train passes that signal. The locking instruments are generally placed in front of the signal-man and over the levers with which they operate. Each block station has one of these instruments for each block, the two instruments at the opposite ends of a block 164 BLOCK SIGNAL OPERATION. being connected by an electric circuit. The code signalling between the stations is accomplished by bell, as in manual blocking. To iUustrate in general terms the manipulation of the signals in the controlled system we will assume there are two block stations, A and B, each provided with the ordinary out-door signals interlocked with the electric apparatus. Prior to starting a train from A the signal-man there asks B to unlock his signal, and when B does so A throws his signal to " safety," allowing the train to proceed toward B. As the rear of the train passes the home signal at A that signal is thrown to *' dan- ger " by the train passing over the track circuit. As soon as his home signal goes to " danger " A throws his lever to its normal position, (" danger ") thereby locking it so that the signal cannot be thrown to *' safety " again without permission from B. A drop slide indicator, or annunciator, forms a part of the electric mechanism, displaying through a slotted opening on the front of the instrument case the for- mulas " free," " locked," and ** train in block," or words to that eflfect, as required. By a system of electric locking, working in connection with the indicators and operated in part by the train through track circuits, B is unable to clear A while there is a train in the block. Normally the indicator displays "locked," but when CONTROLLED MANUAL BLOCKING. 165 the signai is unlocked the word " free " appears on the indicator. When the un- locked signal lever is placed in its clear position the indicator is returned to its normal position, displaying " locked." The block signal is not, however, actually locked until it is returned to " danger.'* The " Sykes," the " Patenall " and the " Union " are among the principal lock and block instruments used in this country. In the Sykes and Union instruments the signal operating levers are normally locked, except when unlocked by the signal- man at the station in advance, while in the Patenall instrument the signals are locked only when the line is blocked by a train, thereby leaving them free to be thrown to either " danger" or " safety," as may be desired, when the line is clear. In the Union instrument the electrical apparatus and the levers are connected elec- trically ; in the Sykes and the Patenall instruments they are connected mechani- cally. The " electric slot " is an appliance for automatically cutting out the block signal from its actuating lever, and is used to automatically return the signal to "danger" behind a train. It is actuated by a track circuit, as heretofore mentioned, placed ahead of the signal, and forms a removable connection 166 BLOCK SIGNAL OPERATION. between the signal counterweight and the signal rod, which connection, if removed when the signal is in the '< clear " position, permits the signal to return to " danger *' by force of gravity. The signal cannot again be placed at " safety " until the signal lever has been placed in its normal ('' danger ") position. This device therefore pievents a signal-man, after having allowed a train to enter a block, from carelessly leaving his signal at " clear," to be accepted by a following train, or from carelessly and prematurely releasing the signal at the rear station while a train is in the block. The electric slot may also be used as the controlling instrument in a controlled blocking system not having electric locking instruments. In this case the slot is operated from the signal station in advance, the connection being normally cut out. When the signal-man at the station in rear asks and is given permission to forward a train, the signal-man in advance cuts in the signal connection so that the signal can be put to '^ clear." When the train enters the block the home signal is thrown to '' danger " behind the train, and it is kept at " danger " while the train is in the block, by means of a track circuit, which keeps the connection cut out so long as there is a train or any portion of a train in the block. There- CONTROLLED MANUAL BLOCKING. 167 fore, neither signal-man has it in his power to give another train a " clear " signal while the block is obstructed by a train. With the controlled system the following points require particular attention : To ensure having the home signal kept at *' clear " during the entire time that a train is passing it, as required, the local track circuit that operates in throwing that signal to danger behind a train must be placed a maximum train length ahead of the signal. If very long trains are handled, as on American coal roads, where a train often has from 80 to 100 cars, (say 2700 to 3400 feet) the circuit should reach at least five-eighths of a mile in advance of the home signal. To effectually guard against the unlocking of the signals in the rear when the head portion of a parted train has passed the advance station and left the rear por- tion in the block, a track circuit, extending throughout the block, as in automatic blocking (page 183) should be used, to connect the locking instruments at one end of the block with the electric locks at the other end ; otherwise, the passage of the train into the block in advance would enable the signal-man to unlock the signals at the rear station, while the block was obstructed by the rear portion of the preceding train. At stations where there are cross-overs, the cross-over switch points should be 168 BLOCK SIGNAL OPERATION. electrically connected with the locking instruments governing the movements in both directions, the circuits being so arranged that both instruments will be locked while a cross-over switch point is set for the side movement, or either main track is fouled, and that the instrument governing a track will be automatically released, as soon as the train is clear of that track and the switches are set for the main track movement. Great care must be taken by the signal-man at a station where switching is done on the main track, or where a main track can be otherwise fouled, to see that the track is clear before a train is accepted for it, especiaUy if the locking instru- ment at that station, and which controls the signals at the rear station, is not auto- matically interlocked with the switches. In the case of switching, the signal-man must not accept a train until he is notified by those in charge of the switching that the main track is clear of cars, and that the switches are set for the main track movement. This applies to all forms of blocking. All main track switches at a block station should be so interlocked (electrically) with the signal locking instruments that when a train on a siding fouls the main track, or a switch is set for a side movement, the signal-man there cannot give OONTROLLED MANUAL BLOCKING. 169 permiHsion to the station in the rear to let a train come forward. Or, in other words, at a station where there are sidings, cross-overs, junctions, etc., and especially if switching and the making np of trains is done on the main track, the signal locking instruments at the station should be electricaUy controlled by a track circuit embracing the main track at all points where it can be occupied by trains or cars, or fouled by trains on sidings, or broken. As a general proposition, the controlled system may be summed up thus : To ensure absolute safety for the main tiack in a block, including the territory for at least 1,000 feet ahead of the home signal at the station in advance (or a greater distance on a down grade), the main track switches at such advance station (including those within the 1,000-foot limit), and all outlying switches in the block, must be electrically interlocked with the block station in the rear, so that the signals at the station in the rear, which control the entrance to the block, can- not be placed at " clear " when the main track is occupied, or is fouled by a train on a side track, or when a main track switch is thrown for a side movement, or a main track '' back up " signal is set for a backward movement. This system applies only to the operation of trains under the absolute block system. CONTROLLED MANUAL BLOCKING. 171 New York Central and Hudson Biver Eailroad Company's Rules for Oper- ating Controlled Manual Blocking on its Four Track Line. The signal equipment of the New York Central & Hudson River Railroad con- sists of the ordinary out-door signals, as noted in the operating rules of that com- pany, interlocked with signal-controlling lock and block instruments, as described on pages 163 and 164. RULES. A block is a portion of track lying between two block towers, and each block will be operated independently for passenger and freight tracks, and for east and west bound trains. All signals are of the semaphore pattern with arms extending to the right of the post, as viewed from approaching trains. They are divided into four classes, namely : advance, home, distant and dwarf signals. Where signals are on bridges, those for passenger tracks have been made higher than those lor freight tracks. Posts are placed over the tracks which they govern, except ag stated in general notices and their accompanying blue prints. (The arrangement of signals on bridges is shown in the figure on the opposite page.) 172 BLOCK SIGNAL OPERATION. At block towers where there is no interlocking, there is a one-arm post for each main tracks located on the bridge directly over the track which it governs. At block towers where there are switches controlled by interlocking, there are located a distant, a home and an advance signal for each main track. At all points where there are facing switches in main track, home signals are provided with two arms ; the top arm governing the main or high speed track, and the lower arm all diverging tracks. Where the signals for tracks Nos. 2 and 3 are not on a bridge, a bracket post is used. Where signals for both tracks Nos. 2 and 3 are on a bracket post, the one for track No. 2 is made the higher. When only one arm is used it is for track No. 2. At all interlockings, and at all block towers where the view of the home signal is obscured, a distant signal will be provided for each main track, located not less than 1,600 feet from the home signal. On the home and starting signals (which are painted red, with a white block near the end) the arm in a horizontal position by day, or a red light at night, means ^ danger (stop)/ The arm lowered to a nearly vertical position by day, or a white light shown at night, means ' all clear,' and is authority to proceed to the next signal- CONTROLLED MANUAL BLOCKING. 173 On the distant signals (which have a forked end, and are painted yellow with a black < shaped band near end of blade) the arm in a horizontal position by day, or a green light at night, means 'caution (proceed to the next signal with train under full control).' The arm lowered to a nearly vertical position by day or a white light shown at night means home and starting signals are clear. Dwarf signals govern movements over all switches in reverse direction of traffic and from sidings to the other tracks. The arm in a horizontal position by day, or a blue light at night, means ' danger (stop).* The arm lowered to a nearly vertical position, or a white light shown at night, means * all dear/ and is authority to proceed. 1. Trains running by block signal rules will be governed absolutely by the fixed signals herein described and wUl not observe train rules 86, 87 and 88 ('' time limit '* rules). Trains will be governed during the day by the signal arms and by night by the lights on the posts. 2. All signals must be kept in their normal condition (" danger " or ** caution ")^ except when lowered to allow train to pass, and must be restored to normal position as soon as whole train has passed. 174 BLOCK SIGNAL OPERATION. 3. If a signal-man becomes disabled or is absent from his post, and it is ascertained by the conductor and engine-man, the train must proceed cautiously to the next block, the same as though a caution card had been given. 4. If the telegraph wire or signal bells fail to work, and the signal-man can- not ascertain if the block ahead is clear, the train should be stopped and the conductor and engine-man given a caution card. 5. Should a train be stopped by signal in consequence of a disabled train being in the block ahead, the signal-man will give the conductor and engine-man a caution card, authorizing them to proceed to the point of obstruction. They will then proceed with caution into the block so occupied and render any assistance necessary to move the disabled train and clear the block. 6. In case of failure to get unlocked, after receiving notice from the signal- man in advance that the block is clear and he has plunged to unlock, and acknowl- edging the same, the signal-man should give the conductor and engine-man a clearance card, authorizing them to proceed to next tower. ^, 7. In case of trains passing towers without markers * * * the signal- man must notify towers in rear and advance, as provided in bell code. The signal-man CONTROLLED MANUAL BLOCKING. 175 in advance tower must clear his signals, proyided the block in advance is clear, and display a green and white signal^ which is a notification to the approaching engine-man that his train has parted. The rear signal-man will, in this case, stop the following train, and give the conductor and engine-man a caution card, showing that the preceding train has parted, and that the rear portion will, probably, be found in the block. * * * * 8. Work trains when occupying the main track to do work must inform the signal-man at the last tower passed of their purpose and leave a flagman at said tower. The signal-man must then forward the following train on a caution card marked " work train in block." 9. When the signal 5-4, showing obstructions, has been received, the signal- man shall give conductor and engine-man a caution card and allow them to pro- ceed ten minutes after,departure of preceding train. 10. When it is necessary for a train to cross over to the opposite track, the conductor, before crossing, must notify the signal-man at the block tower before reaching the cross-over to be used. The signal-man must then notify the signal- man at the next block in the direction in which the train is moving, and the train 176 BLOCK SIGNAL OPERATION. shall not cross until the conductor is notified that the signal-man at the block tower in advance has been notified and has answered by the *' all-right " signal, and flagman sent out. * * The signal-man in the advance tower, after re- ceiving such notification, must stop any train approaching on the opposite track and give the conductor and engine-man a caution card, notifying them that the train has crossed over and will be found in the block ahead. If, however, a train is in the block on the track to which the train is to cross, the signal-man must not permit the train to cross over until the train occupying the block has arrived at his tower. 11. When, from any cause, it is necessary to couple two or more trains together andto run them as one * * * * they shall not be separated under any circumstances until the train arrives at the block tower. If they are then separ- ated, each train Fhall be governed thereafter as a single train. 12. Where home signals are not provided with distant signals, signal-men must in no case give the " block clear " signal, nor unlock the tower in rear, until the first train has passed the home signal by 400 yards or more. CONTROLLED MANUAL BLOCKING. 177 13. A signal-man having orders for a train shall display a red signal in €Kldi- tion to the block signal 14. In the absence of any signal, the train must stop, and the cause of failure to display the same must be ascertained. 15. Trains must, under no circumstances, pass signals at " danger," except as provided in block signal rules 3, 4, 6, 6, 7, 8, 9 and 10. 16. When an engine-man finds a signal at *' danger " other than the block sig- nal, such as a distant station signal, or a draw-bridge signal, he must come to a full stop, then pass the signal and run cautiously to the point of obstruction, obtaining thereby the protection of the signal. Bule 95, (flagging rule) however, must be observed by the conductor. 17. The use of the block signals and the rules governing same do not reheve employees in the train service from observing all other rules relative to the protec- tion of their trains. 18. Conductors and engine-men are particularly requested to note the places at which the signal towers are being constructed along the line, so that, when com- pleted and put in use, they can readily locate them. 178 ^lOCK SIGNAL OPERATION. Instructions for Working Lock and Block Instruments and Bell Code. BELL SIGNALS. BELLS MUST BE RUNG SLOWLY AND DISTINCTLY. 1. All right. Yes. 2. Train has cleared. 3. Unlock my lever. Passenger tracks, answer by plunge or ring 5 or 12. 3-1. Unlock my lever. Freight tracks, answer by plunge, or ring 5-1 or 12-1. 4. Train has entered block. Passenger track. Answer 1. 4-1. Train has entered block. Freight track. Answer 1. 5. Block is not yet clear. Passenger track. Answer 1. 6-1. Block is not yet clear. Freight track. Answer L 6. Is train coming to me ? Passenger track ? Answer 1 or 7. 6-1. Is train coming to me? Freight track ? Answer 1 or 7. . 7. No. 8. Testing by inspector. 9. Am going to clean lamps. Answer 1 or 7. CONTROLLED MANUAL BLOCKING. 179 10. Send electrician. When using this signal always give number of tower in trouble. 11. Send mechanical repair-man. When using this signal always give num- ber of tower in trouble. Signal-men receiving 10 or 11 bells, with number of tower, will repeat signal to nearest telegraph station. 12. Have plimged. Passenger, answer 12. If answered by 1, give train a clearance card and allow it to proceed, announcing it by 4. 12-1. Have plunged. Freight, answer 12-1. If answered by 1, give train a clearance card and allow it to proceed, announcing it by 4-1. 5-4. Obstruction. Danger signal. Stop all trains. Answer by 6-4. 4-5-1. Train on track No. 1 broken in two. 4-5-2. Train on track No. 2 broken in two. 4-5-3. Train on track No. 3 broken in two. 4-5-4. Train on track No. 4 broken in two. 2-2. Stop and examine train. Passenger, answer 2-2. 2-2-x. Stop and examine train. Freight, answer 2-2-1. 180 BLOCK SIGNAL OPERATION. 2-3-2. Previous signal given in error. 4-3. Have train to let out of siding. To be answered by 5 or 5-1 or 4-3. 4-4. Is track clear to cross train over to opposite tracks between these towers ? To be answered by 4-4. 5-6. Train has gone on siding and switch to main Une is closed. If under- stood, repeat 5-6 to sender. To Beoeive Train (Block Being Clear and Signals at. Danger). — In answer to 3 taps of bell, pull the plunger on the instrument out firmly and carefully ; this im- locks the lever in the next tower and locks up the plunger. To Forward Train. — Ring 3 strokes on bell to man in advance of train. As soon as lever is unlocked by him ring 1 stroke and clear signal. Place signal at ^' danger " as soon as train has passed it, and ring clear to man who sent train to you. Signals must be answered immediately. Do not tamper with the instruments. The unnecessary use of the bell, or the use of signals not authorized, is strictly forbidden. In case of trouble call mechanical or electrical repair-man. CONTROLLED MANUAL BLOCKING. 181 New 7ork Central & Hudson Biver R. R. Co. DIVISION. CAUTION CARD. Tower, 189. Jf. To Engineer _. Engine. Train Jfo*. jon. Track. PROCEED WITH CAUTION. OPERATOR. NOTE.— The Engineer receiving thia card, duly dated, timed and signed, will ran to the next signal or point of obstniction with train onier complete control, and as he knows the way to be clear, and on completion of trip will send the card to this of&ce. Superintendent The '' caution " card is of green paper, as a reminder to those using it that the movement is to be made under the " caution " or green signal. 182 BLOCK SIGNAL OPERATIOif. New 7ork Central & Hudson River R. E. Co. DIVISION. CLEARANCE CARD. .^Tower 189. .M. To Engineer. Engine, Train Jfo.. .on. Track. Signal cannot he Cleared; Proceed with Caution to the next Signal Tower* OPERATOR. NOTE.— This card must not be used except in case of failare of block signals and when section has been duly reported clear by the operator at advance tower. 'I he engineer receiving it, duly dated, timed and si 'ned. will run to next signal with train under full control, and on completion of trip will send card to this office. Superintendent. CHAPTER XII AUTOMATIC BLOCKING. Automatic block signals are usually operated through the agency of electric- ity alone or of a combination of electricity and compressed air, by the passage of trains into and out of the block. Signal-men are not employed in the manipulation of these signals. A track circuit is generally used in automatic blocking, for conveying the electric current to the signals, and this is the only method that will be referred to here. In arranging a track circuit, a gravity battery is commonly used, and is placed at the advance end of the block. A relay and the signal are placed at the 184 BLOCK SIGNAL OPERATION. other end. Each line of rails is connected with a pole of the battery. The current passes along the rails of one side of the track, through the relay, thence along the rails of the other side of the track, thus forming a circuit. The relay controls a local circuit which works an electro-magnet, which in the simple electric system actuates the signal, and in the electro-pneumatic system permits compressed air to actuate it. The electric power may be generated by a dynamo, and, indeed, this is the preferable method. The use of storage batteries in electro-pneumatic interlocking permits of a closer regularity of the quantity and pressure of the current, and re- sults in considerable economy in operation. As in other methods of blocking the line is divided into blocks or " circuits," the track of each block being insulated from the tracks of adjoining blocks. To insure good connections the rails in a block are joined at their end with wire to bridge the fish plates, the wire being rivited to the base of the rails. It is sug- gested that the wires be rivited to the web of the rails, as this would cause less injury to the rails. The insulation from each other of the rails of adjacent blocks is accompUshed by inserting a piece of leather board, fiber or other insulating sub- AUTOMATIC BLOCKING. 18r> staDce between the ends of the rails, and using wooden fish plates or splice bars to connect these rails. WIRED JOINT. maUIATED JOINT. There are two plana under which antomatio block signals are operated : 1, the " ncn-mal-Bafety " plan, that in which the signals always show " clear " unless 186 BLOCK SIGNAL OPERATION. the block ia obstructed either by a train or otherwise ; 2, the " normal danger " plan, that in which the signals are at " danger " at all times except when cleared by an approaching train, which can be done only when the block is clear of trains and other obstructions. When the head end of a train enters an automatic electric block the current short circuits (that is, it takes the shortest path back to the battery) through the axles of the locomotive or car, and is thereby cut off from the relay, which then breaks the local circuit operating the signal. When the signal is passed by the rear end of the train, it goes to the " danger " position. In the " normal safety '* plan, when the train passes out of tlie farther end of the block the signal again goes to " safety." In the " normal dan*^er " plan the currents are so arranged that the signal sets at " danger " until it is again cleared by an approaching train. Automatic block signals are applicable to junctions, railroad crossings and draw-bridges if manual interlocking ia used. Separate signals are provided for the interlocking. The same rules ap})ly to tlie block signals here as elsewhere. If the interlocking and block signals both show " clear " trains may proceed with speed. At ii junction, where the route diveiges, the block signal will show ** clear '* when AUTOMATIC BLOCKING. 187 there is no train in the block ahead on the main line and the interlocking signal is lowered for a train to continue on the main line, or when there is no train in the block ahead on the branch line and the interlocking signal for the branch is lowered. The Union Electro-Pneumatic System. The general features of the electro-pneumatic system, as developed by the Union Switch & Signal Company, are : 1, a rail circuit with its batteries and relays ; 2, an air compressor with its pipes to the signal posts, and 3, the signal posts them- selves with their arms, air cylinders, and electrically-controlled valves. Two semaphore signals are placed on a post about 50 feet to the rear of each section. The upper one, according to the general practice of to-day, is the " dan- ger " or home signal, is painted red, and governs the section immediately ahead; the lower one is the " caution " signal, is painted green and works in harmony with the " danger '' signal of the next section. Each semaphore is operated by a cylinder three inches in diameter, fitted with a piston, the rod of which is so connected as to move the signal to its " clear " position when air pressure from the main pipe line is applied to the piston, by means of the electric valves, that 188 BLOCK SIGNAL OPERATION. being the position of tho signals when the track is clear for the movement of trains. Each signal blade carries an appropriately colored lens, which covers a light when the blade is in the horizontal position, showing red if it is the upper signal, and green if it is the lower signal. A white light is exposed when the signal is in position to indicate that the track is clear. The system as above described is that of the duplex or overlapping blocks. If at any signal post (A) the top arm is lowered, and the bottom arm is horizontal, it indicates that the block to the next signal post (B) is clear, but that the second block (B to C) is occupied. If both arms are lowered, the track is clear from A to C. The air compressors may be of any type, but preferably not of that used with the ordinary air brake, which type has been found to be, when used for this purpose, uneconomical in steam consump- tion. They are usually placed in pairs, so that if anything should happen to one the other can be thrown into service immediately. A 2-inch pipe for conveying the air is carried directly from the compressor along the right of way of the railroad, and wherever a signal occurs a small branch pipe connection runs from the main air pipe to the signal cylinder. An auxiliary reservoir is placed at the bottom of each post for the purpose of collecting any moisture which may form in the column A UTOMA TIG BLOCKING. 189 of air. This is done to avoid having the signal cylinder frozen up. The air pres- sure should be maintained at about 60 lbs. to the square inch. Following are the rules of the Pennsylvania Bailroad, issued January 30, 1892, for the operation of the Union electro-pneumatic block system on the New York division of that road : " These signals consist of two arms on each post ; the upper is the home signal for the block ; the lower is the distant signal for the home signal of the next block ; they are located at the begiuning of each block section. ''The normal position of these signals is at ^ clear.' A train entering a block section will automatically set them ; the home at ' danger/ and distant at * caution.' " A train finding a home signal at ' clear ' and distant signal at ' caution ' may proceed, expecting to find next home signal at ' danger.' '' A train finding a home signal at 'danger ' must stop before passing it. After waiting one minute, it may then proceed with caution, expecting to find train on block. Should it find no train on block, report to Superintendent from first tele- graph ofiice, giving number of signal passed at ' danger.' " 190 BLOCK SIGNAL OPERATION. The Hall Automatic Signal System. In the Hall electric block system the signal instrument is contained in a case (popularly known as a " banjo") mounted on an iron or wooden post, the length of which may be varied to suit conditions. Within the case is mounted a disk of red silk, with a red glass on the opposite end of the arm carrying the disk. By day a white glass, in the back of the home signal case, is exposed through the glass covered aperture in front, so long as the large red disk is held out of sight. The front of the case being dark, the indication of safety is thus shown by a white disk in the center of a dark ground. The falling of the large disk before the glass produces the dauger signal, by showing red, and at the same time cuts oflF the strong contrast formed by the pure white Ught disk in the center of the dark case. The front opening is larger than the disk proper, so that when the signal is at "danger" there is a band of white shown around the disk. At night the cleai* signal is obtained direct from a lamp, showing a white light through the small opening in the top of the case. On the signal assuming the dan- ->mmw//wmy standard Signal Gise. . THE HALL AUTOUATIC SIGNAL. 192 BLOCK SIGNAL OPERATION. ger position a ruby glass lens is carried up before the small opening by gravity, giving a red light. When desired, the dear night indication may be green instead of white. In this case the single glass disk, above described, is replaced by a double disk, one green, the other red, these being placed at right angles to each other. The distant signal is substantially of the same construction, but the disk is green, and the face of the case may be painted white, to distinguish this signal from the home signal. When at danger the green disk presents a strong contrast to the white surrounding case. At night a green lens is used to indicate ''caution." At junctions, cross-overs, sidings, etc., a switch instrument is used, which, through its electrical connections, causes the block signal to display " danger " when a switch is not set for the required movement. A visible indicator is placed at main track switches to warn a trainman desiring to open a switch to let a train out on the main line. This indicator will show " danger " if an approaching train shall have passed a point 1,000 feet or more in advance of the home signal next back of the switch. If the main track is clear and the trainman therefore opens the switch, this operation sets at ''danger'* J UTOMA TIG BLOCKING. 193 the main track home signal of the block in which the switch is situated. The arrangement of the parts and of the circuits of the indicator are such that any failure will cause the indicator to assume the danger position. The Lake Shore & Michigan Southern Railway Company operates the Hall elec- tric block signals on its Michigan division under the following information and rules : *The display of a red disk or red banner by day, or a red light by night, indi- cates * danger— stop.' " A white light displayed by night, or the absence of a red disk or red banner by day, indicates ' safety — proceed.' '' A small portion of the disk will be visible when the signal is at ' safety,' at the upper left hand edge of the opening in the signal case, and serves to show that the disk is there and connected with the signal instrument. '' Signals of the banner type are placed 225 feet within the blocks they respec- tively control, and should turn to ' danger ' (if not already in that position), ahead of an approaching train when the first pair of wheels enters the block, the entrance of whiph is marked by the signal post. " A signal will indicate * danger ' as follows : 194 BLOGE: SIGNAL OPERATION. "First. — When a traia has passed it and has not passed out of the block which it controls. " Second. — When any switch in that block is open. " Third.— When a car or train stands on a siding, between the fouling point and main line, the position of such fouling point being indicated by a post marked " Fourth. — When the track is broken by removal or breaking of rail. " Fifth. — Whenever either switch of any cross-over leading to the main track on which the signal is located, is open. " A train finding a signal at ' danger/ shall come to a stop before reaching it, and shall wait there two (2) minutes (unless the signal shall clear in less time) before proceeding. "If the signal goes to 'clear,' the train may proceed at the usual rate of speed ; but, if the signal shall not have cleared, then the train at the expiration of two (2) minutes shall, after placing two torpedoes on rail (ten yards apart — one rail length), 50 feet from the rear of train, proceed cautiously and under full con- trol, expecting to find the track obstructed or broken. A UTOMA TIC BLOCKING. 195 '' Trains entering a block, as provided above, will be held responsible in case of an accident caused by overtaking a preceding train. '* No car or train shall stand on a siding within fouling distance of the main track. " Any train leaving a part of the train in one block to do work in the next block, or making any unusual stop, must observe flagging rules, protecting the train as though there were no block signals in operation. " A train which has taken a side track to allow another train to pass, shall not come out on the main line again until ten (10) minutes after the train has passed. " A train desiring to come out on to the main line from a siding or cross-over, shall open the switch and wait three (3) minutes before proceeding, to allow a train which may have passed the preceding signal, time to run from the signal to such switch. " When the block signal light is out, the conductor wiD notify the division superintendent from the first open telegraph office at which the train stops, giving number of signal and its location. " The abs(Mice of a block signal light or an improperly displayed signal, will be considered and treated as a danger signal. 196 BLOCK SIGNAL OPERATION, " When the number of a signal is coyered, it indicates that the signd is out of service, and trains will proceed cautiously without coming to a stop. " Conductors will report to the division superintendent, on blank forms pro- vided for the purpose, from the first open telegraph office at which the train stops, all delaVs caused by signal, giving number of signal. At the end of a run, conduc- tors will fill out blank report to correspond with any stops which they may have been obb'ged to make by reason of the signals, and send them to the division sup- erintendent by mail.** Following are extracts from the rules for operating the Hall electric block signal system in the Chicago terminal district of the IlUnois Central Bailroad : The signals are placed on bridges spanning the tracks, or on single posts. Where a bridge is used a train is governed by the signal standing over the right hand rail of the track occupied by the train. Signals on posts are plac3d imme- diately to the right of their respective tracks. A train finding a signal at '' danger " will stop and wait one minute or two minutes (depending on tiie instructions for that particular point which are given in the working time-table) before proceeding, unless the signal earlier returns to • « A UTOMA TIC BLOCKING. 197 *' safety^" A train passing a signal at *' danger " after waiting the required time must proceed under control, expecting to find a train or open switch in the block. Green block signals may be passed without stop when the view is clear. A train passing a gree^ignal most pWd under conkol. eating to find a pre- ceding train in the block. Whenever the view is obscured by fog or otherwise, trains must not proceed until the signal is known to be clear, or after waiting the required time, a flagman is sent in advance until a clear signal is reached. When for any reason a GOgnal is out of service the disk will be covered. Trains finding signals out of service will proceed with caution until a clear signal is reached. Through passenger trains (on tracks and at points indicated on time-table) finding a block signal at danger, may pull up to the station, do their station work, and proceed in the usual manner after a stop of two minutes has been made. Suburban trains finding signals at '* danger," when such signals are located not more than 600 feet beyond the point at which the station stop is made, will, unless 198 BLOCK SIGNAL OPERATION. the signals earlier return to '^ safety/' remain at the stations the required time before proceeding. Two stops at such stations are unnecessary. Cars and engines standing on a siding must clear the fouling point with main track two full rail lengths, as to stand nearer sets the main track signals to " dan- ger. Each switch is protected by a bell which will ring when a train is approaching it in the block, and the switch must not be opened until the train has passed. CHAPTER XIII. MACHINE BLOCKING FOR SINGLE TRACK LINES. Machine bloddng, which has not as yet been introduced extensively in this country, appears to offer the safest method of single track blocking yet devised. The principle involved in machine blocking is a modification of the staff sys- tem. Staff or tablet machines are used, one being placed at each end of each block, and these machines are so constructed that the withdrawal of a staff or tab- let from one machine automatically locks the apparatus so that a second staff or tablet cannot be obtained at either end of the block until the first one is restored to one or other of the two machines of the block. In England, single track lines were at first operated by means of the '' pilot guard," a method still employed there on a few short branch lines. 200 BLOCK SIGNAL OPERATION. Under this arrangement, a pilot accompanies every train, when possible, but when it is necessary to start two or more trains from one end of a section that is under the pilot's control, before a tram is to be started from the other end, the pilot must furnish the conductor in charge of each train not accompanied by him- self, with a printed " pilot ticket " (see page 235) properly filled out and signed, and he must personally give the order for starting the train and must himself accompany the last train. The next step was to introduce the working by train staff, and this was after- ward extended to the train staff and ticket system, to meet the case of more than one train passing in one direction before a train was required to be run in the opposite direction. By this system a train staff or a train staff ticket is carried with each train, and without a staff or ticket no train is allowed to run in the section. The staff itself is a piece of wood or of hollow metal. The ticket, of convenient size, is a printed form authorizing the engine-man, after seeing the train staff for the section, to proceed between the stations named on the ticket. Each staff has engraved or marked on it the name of the staff station at each end of the one section to MACHINE BLOCKING FOR SINGLE TRACK LINES. 201 which it applies. The staffs, boxes and tickets for the different sections are painted or printed in different colors, and the staffs of adjoining sections are different in shape. The train tickets are kept in a ticket box at the staff station, and the key to unlock the ticket box is the staff itself. The moving of trains by the staff system is about as follows : Supposing that a staff section extends from A to B, and that there are several trains at A to move to B. Each of these trains except the last takes a ticket. The last train takes the staff. The conductor and the engine-man of each preceding train must see the staff, however, before leaving A ; this is a precautionary measure to prevent acci- dent through trains entering the block when the staff is perhaps held by a train coming in the opposite direction. The party finally taking the staff locks the staff ticket box before leaving. This form of working, with the additional protection afforded by the block signalling, remained in force for a considerable time on single track lines. In more recent years it has to a large extent been superseded by the electric train staff (or tab- let) system, the advantages of which are (1) that a train can be sent for^ ard from either end of the section without awaiting the arrival of the staff from the other end» 202 BLOCK SIGNAL OPERATION. a frequent source of delay under the old method, and (2) that greater security in working is obtained on account of the impossibility of withdrawing a staff from the machine at either end of the section without the concurrence of the signal-man at the other end. The machines in general use are the Webb & Thompson electric train staff machine and the Tyer train tablet machine. A machine is placed at each end of the block, the two machines being connected by an electric circuit. In each block station therefore there will be two independent machines, not con- nected in any way ; one of these is for the block in the rear and the other for the block in advance. Thus block station B would have one machine connected with a machine at A, and another machine connected with a machine at C. The opera- tion of either style of machine is simple, and practically the same as that of the other. The Webb & Thompson train staff machine consists of an iron pillar with a vertical slot through nearly its entire length, in which is a supply of staffs. For sending more than a single train in one direction before the arrival in each case of the preceding train at the staff station in advance, a machine with a separate slot for holding a special staff is used. The head of the machine, called the locking MAGmHE BLOCKING FOR SINGLE TBAUK LINES. 203 case, Gontaiiis the electrical app&ratns for manipalatiiig the machine, and, in the caBe of a special staff machine, the staff ticket box. Only one staff can be vith- dravn at a time from the two machines governing a block, and this only with the WEBB A THOUPBOH TBAIV BTITV HAOHIKS. consent of the signal-man at the receiving station who alone oontrols the ata& at the sending station. Another staff cannot be removed from either machine until the one alraadj oat is restored at one or the other end of the block. Thus, when 204 BLOCK SIGNAL OPERATION. a staff has been taken out at station A another cannot be taken out at* station B, nor can a second staff be taken out at A until the staff previously withdrawn has been restored to the machine at either A or B. A staff can be replaced, however, in a machine without previous communication with the opf>osite end of the block. Communication between block stations is effected by means of the usual electric bells, a bell being attached to each machine. Following is the method of working the staff machine : Let A and B represent two block stations. Before starting a train from A to- wards B the situation with reference to the block is ascertained by means of the bell code. If the block is clear of trains and obstructions, B, when asked, unlocks A's machine. This allows A to withdraw one staff, which is given to the engine- man, who, on the arrival of the train at B hands it over to the signal-man there to place in his machine. As neither of the machines governing the block can be unlocked while the engine-man has the staff, it is of course impossible to furnish a staff for another train untU he has dehvered his staff. It is not necessary to place staff machines at block stations not at passing sidings, as all that the staff is intended to do is to govern the non-meeting move- MACHINE BLOCKING FOB 8IN0LE TRACK LINES. 205 xuents. When there are intermediate block stations, staff machines with special staffs and tickets (in addition to the regular ctaffs) may be used. As the principal function of the intermediate block stations is to govern the non-following move- ments, these stations would be equipped with signal bells and out-door signals only. For example, suppose a ti*ain is moving from A to D, at each of which points is a passing siding; also that there are intermediate block stations B and G. Train staff machines are located at A and D. The train receives a staff at A, and carries it to D, where it is exchanged for another staff. The block stations at B and are merely spacers for the purpose of keeping following trains apart. If there is more than one train to proceed towards D the special staff and train tickets are used. Each train except the last takes a ticket instead of a staff and goes forward when the A-B block is clear. The last train takes the staff and any remaining tickets. On the arrival of the last train at D all the tickets are locked up in the machine, and the special staff is placed in its slot, which action restores the machines at A and D to their normal, or locked, condition. Tyer s train tablet machine is operated similarly to the Webb & Thompson 206 BLOCK SIGNAL OPERATION. machine. A metal tablet is used instead of a staff, the tablet being simply a train staff in another form. Besides being absolute blocking instruments these machines are adapted to the protection of drawbridges and junctions, and would seem to make such places as safe as human foresight can make them. For ordinary block working it would be a serious hindrance to traffic if all trains were required to slow down or stop to allow the engine-man to receive and deliver each staff. Devices have therefore been made for taking the staff while the train is running at good speed. The method of exchanging train staffs or tablets with a train in motion is similar to that of catching mail bags by moving trains, an appUance similar to the mail catching device being used. The apparatus is double, having a delivering as well as a receiving end, so that a staff or tablet can be de- livered mechanically at the block station at the same time that another is taken on. To prevent injury to the staffs or tablets in making the exchange, they should be put in a stout leather case. In arranging the exchanging appliances on locomo- tives and at block stations, care should be taken to get the appliances all in line, that is, the same distance from the center of the track, so as to ensure their proper action. MACHINE BLOCKING FOR SINGLE TRACK LINES. 207 BEGULATIONS OF THE LONDON AND NOETH WESTEKN RAILWAY FOR WORKING SINGLE LINES OF RAILWAY ON THE ELECTRIC TRAIN TABLET OR ELECTRIC TRAIN STAFF SYSTEM. 384. The object of the system of train tablet or electric train staff signalling is to prevent more than one train being between any two tablet or staff stations ai the same time, and, when no train is in the section between two tablet or staff stations, to admit of a train being started from either end. This is accomplished by eveiy train carrying a train tablet or train staff, one tablet or staff only being ob- tainable from the tablet or staff instruments of the same section at the same time. 385. A train tablet or train staff most be carried with each train, and no train must leave any tablet or staff station, except as provided in rules 391, 392, 403, 406 and 407, unless the engine driver (as explained in rules 384 and 391) is in possession of the tablet or staff for that portion of the line over which he is about to travel Each train tablet and train staff has engraved or marked on it the name of the 208 BLOCK SIGNAL OPERATION, • tablet or staff station at each end of the section to which it applies, and the tablets and staffs of adjoining sections are different in shape or color. 38G. The system under which the electric train tablet and electric train staff instruments are to be worked, and the mode of indicating the description of approaching trains, will be laid down in the code of regulations suppUed to signal- men or exhibited in the signal boxes and at tablet and staff stations for the guidance of the signal-men or other persons in charge. 387. The " danger " signal must always be kept exhibited at all the fixed signals at tablet and staff stations, except when it is necessary to lower or turn them off for a train to pass ; and before any signal is lowered or turned off, care must be taken to ascertain that the Une on which the train is about to run is clear and properly protected. At places which are not tablet or staff stations, the '^ all right " signal must, un- less special instructions to the contrary are issued, be kept exhibited at all the fix- ed signals (where such signals are provided), except when required to be placed at ** danger " for the protection of trains having to stop in the section, or any other ob- struction that may exist on the main line which the signals are intended to protect. MACHINE BLOCKINO FOR SINGLE TRACK LINES. 209 When trains which have to cross each other are approaching a tablet or staff station in opposite directions, the signals in both directions must be kept at *' danger/' and when the first train has been brought to a stand, the home signal applicable to such train may be lowered to allow it to draw forward to the station or to the starting signal, and after it has again come to a stand, and the signal- man has seen that the line on which the other train will arrive is quite clear, the necessary signals for that train may also be lowered. Where starting signals are provided, except in the cases referred to in rules 402, 40 J, 405, 406 and 407, the starting signal must not be lowered until a train, tablet or train staff has has been obtained for the train to proceed to the tablet or staff station in advance. 388. No train must foul the signal line after permission has been given for a train to enter the other end of the section ; nor must a train foul the single line outside the home or advanced starting signal for shunting purposes, unless the engine-driver is in possession of the tablet or staff for the section so fouled, except as follows : Exception. — On those lines where shunting staffis an^ provided, so interlocked 210 BLOCK SIGNAL OPERATION. with the tablet or staff mstroment that the shunting staff cannot be obtained when permission has been given for a train to approach from the opposite end of the section, and permission cannot be given for a train to approach from the opposite end of the section, except when the shunting staff is in connection with the tablet or staff instrument — ^unless instructions to the contrary are issued, an engine- driver, when in possession of the shunting staff, and when authorized by the signal-man to do so, may proceed with his engine on to the single line at the end of the section to which the shunting staff applies, as far as is necessary for shunting purposes at the tablet or staff station, without being in possession of a train tablet or train staff. 389. The signal-man or other person in charge of the tablet or staff working for the time being is the sole person authorized to take a tablet or staff from, or place a tablet or staff in, the instrument, or (except where some other person is specially appointed to the duty) to receive a tablet or staff from, and deliver it to, the engine-driver, who, whilst it is in his charge, must carry it in the socket or other place provided for the purpose. MACHINE BLOCKING FOR SINGLE TRACK LINES. 211 390. When a train arrives at a tablet or staff station and the signal-man has received the train tablet or train staff, he must ascertain that the whole of the train is clear of the section, and then deposit the tablet or staff in the instroment, except as explained in the following clause : If the train should pass with tail lamp missing or out, the signal-man must send the ''train passed without tail lamp " signal (as laid down in the block tele- graph regulations) to the tablet or staff station on each side of him, but must not deposit the tablet or staff in the instrument. The signal-man at the tablet or staff station in advance must stop the approaching train and ascertain from the guaid whether his train is complete. If the train is complete the signal-man must give the '' train out of section '* signal, and the signal-man at the tablet or staff station from which the '' train passed without tail lamp " signal was sent must then deposit the tablet or staff in the instrument and give " train out of section " signal to the station in rear. Should the signal-man become aware as the train passes iuto the section in advance, or on receipt of information from the signal box in advance, that a portion of the train has been left behind, steps must be taken to 212 BLOCK SIGNAL OPERATION. clear the obstruction before any other train is allowed to enter the section, the first available engine at either end of the tablet or staff section being detached from its train for the purpose of clearing the line. If the engine which is to remove the obstruction starts from that end of the section where the train tablet or train staff is out of the instrument, the signal-man must hand such tablet or staff to the engine-driver and instruct him to proceed cautioualj to the vehicle or vehicles which have become detached, and remove them to the most convenient end of the section. If, however, the relieving engine is to start from the other end of the section, then the train tablet or train staff must (after all arrangements are made) be placed in the instrument, so that one may be withdrawn at the other end of the section to enable the relieving engine to proceed to the vehicle or vehicles which have be- come detached, and remove them to the most convenient end of the section. In either case, the signal-man at each end of the section must communicate with each other and arrive at a clear understanding how the obstruction is to be removed. Under no circumstances, except as provided in the previous clause and in rules MACHINE BLOCKING FOR SINGLE TRACK LINES. 213 402 and 403, must a train tablet or train staff be transferred from one train to another with oat being passed through the instrument and dealt with in accordance with the regulations. 391. When a train has more than one engine in front, or when two or more light engines are coupled together, the train tablet or train staff must be shown to each engine-driver, and delivered to, and carried by the driver of the last engine. When the train has also an engine in the rear, the train tablet or train staff must be shown to the engine driver or engine-drivers in front of the train, and delivered to, and carried by the engine-driver in the rear of the train. Trains must only be assisted by an engine in the rear on those sections of the line where special in- structions are issued giving permission for this to be done. An assisting or banking-engine must n6t in any case leave the train it is assist- ing or banking, except at a tablet or staff station, unless authorized by the super- intendent of the line under special regulations. 392. No engine-driver with a train must, except as provided in rules 433, 406 and 407, leave a tablet or staff station until he has received the proper train tablet or train staff for that section of the line over which he is about to travel, or it has 214 BLOCK SIGNAL OPERATION. been shown to him as required by role 391. After receiiring the tablet or staff, the engine-driyer must not proceed until all the necessary fixed or other signals have been exhibited. He must keep the train tablet or train staff under his own charge (except as explained in rules 397, 402 and 403) until he reaches the end of the sec- tion, when he must give it up to the signal-man or other duly authorized person. Engine-drivers mufit be extremely careful not to take the tablet or staff beyond the station at which it ought to be 1^. 393. Except as provided in rules 403, 406 and 407, an engine-driver will render himself liable to dismissalif he leaves a tablet or staff station without the train tablet or train staff for that section of the line over which he is about to run ; or unless it has been shown to him as required by rule 391. 394. At tablet or staff stations which are approached by trains in opposite directions at the same time, the line must be considered clefiu*, and the " train out of section " signal must, unless special instructions be issued to the contrary, be given immediately the last vehicle (with tail lamp attached) has been drawn clear on to the loop line, except in cases where no train is approaching or requires to proceed in the opposite direction, when the '' train out of section '' signal must not MACHINE BLOCKING FOR SINGLE TRACK LINES. 215 be given to the tablet or staff station in the rear until the train has passed the starting signal and is proceeding on its journey, or has been shunted clear. At tablet or staff stations which are not approached by trains in opposite directions at the same time, the line must be considered clear, and the " train out of section " signal must be given immediately the last vehicle (with tail lamp attached) has passed the starting signal and the train is proceeding on its journey or has been shunted clear. When practicable, signal-men must themselves see the tail lamp on the last vehide before giving the " train out of section " signal to the tablet or staff station in the rear ; but in cases where a train does not pass the signal-box before shunting clear, or when a train has been brought to a stand, clear on the loop line, before reaching the signal-box, and it is necessary to give the '^ train out of section " signal to the tablet or staff station in the rear, the signal-man must be informed by the guard or some other responsible person, that the whole of the train has arrived with the tail lamp attached, before giving the " train out of section '' signal to the tablet or staff station in the reai*. 395. The engine driver of a ballast train that has to do work on the line must be told, when receiving the train tablet or train staff, to which end of the section 216 BLOCK SIGNAL OPERATION. it is to be taken, and at what time it is to be there, in order to clear the line for the next train. When a ballast train in possession of the train tablet or train staff is at work on the line, it will not be necessary to send out flagmen to protect it, as directed in rule 321. 396. When it is necessary for a plate-layers' lorry * to go through any of the tunnels speciaDy enumerated in the appendix to the working time table as coming within the application of this rule, the ganger or leading man in charge of the lorry must be in possession of a train tablet or train staff, and the lorry must be signalled on the train tablet or train staff instruments, in accordance with the authorized code. Should the lorry after passing through the tunnel be removed from the rails before reaching the next tablet or staff station, the ganger or leading man must take the tablet or staff to the signal-man at the end of the section nearest to him, except when the tablet cannot be restored to the instrument from which it was obtained, in which case it must be taken to the tablet station at the * Tiftckmeo's band cat. MACHINE BLOCKING FOR SINGLE TRACK LINES, 217 opposite end of the section, and he must inform the signal-man that the lorry is clear of the line and hand the tablet or staff to him. Lorries passing through aU other tunnels must be protected soldj by the plate layers'* own signals. 397. Points giving communication between the sidings and the main line controlled by the train tablet or train staff cannot be opened without the tablet or staff for that section of the line where the siding is situated, and the tablet or staff cannot be removed until the points have been placed in the proper position for trains to pass upon the main line, and securely locked so as to prevent vehicles passing from the sidings on to the main line. On arriving at a siding, the points of which are controlled by train tablet or train staff, the engine-driver must hand the train tablet or staff to the guard or man in charge of the siding, to enable the points to be unlocked. When the necessary shunting has been completed, and the points have been placed in the proper position for trains to pass upon the main line, the guard or man in charge * Trackmen. 218 BLOCK SIGNAL OPERATION, of the siding must return the tablet or staff to the engine driver, and the latter must not proceed on his journey until he has obtained possession of it. 398. The working time tables or appendices, issued for the guidance of the servants, will contain a list of the tablet and staff stations and of the siding points controlled by the train tablets and train staffs. 399. When a special train has to be run without previous printed or written notice, the usual special train tail signal must, if possible, be attached to the pre- ceding train for the guidance of the plate-layers and others employed of the line, but as special trains or engines have frequently to be run without previous notice of any kind, it is necessary for the staff along the line to be, at all times, prepared for such extra trains. A special tail board or tail lamp need not be carried by preceding trains of which previous printed or written notice has been given. 400. On train tablet or train staff sections where a greater number of trains are run in one direction than in the other, causing the train tablets or train staffs to accumulate at one end of the section, the tablets or staffs must, when necessary, be transferred (by the man appointed by the telegraph superintendent for the pur- MACHINE BLOCKING FOR SINGLE TRACK LINES. 219 pose,) from the tablet or staff instrument at which the tablets or staffs accumulate to the instrument ut the other end of the section. The number of tablets or staffs removed by the man appointed by the telegraph superintendent must be recorded by him in the train tablet or train staff register provided for the purpose, and the signal-man must sign the entry and insert the time at which the transaction takes place. The signal-man at the tablet or staff station to which the tablets or staffs are transferred must, immediately on receipt, compare the number recorded in the line- man's register with the number of tablets or staffs received, and when he has satis- fied himself that the number is correct, and that the tablets or staffs have been deposited in the proper instrument, he must sign the register, and insert the time at which the transaction takes place. Note. — The number of electric train staffs removed by the lineman must always be an even number, that is 2, 4, 6, and so on. 401. If a train tablet or train staff should be damaged so that it cannot be deposited in the instrument, the lineman must be at once sent for, and on his arrival he must, in the presence of tho station-master or other person in charge, 220 BLOCK SIGNAL OPERATION. adjust the instrament so as to admit of the tablet or sta£f working being carried on without the damaged tablet or staff, which must be taken away by the lineman for repair (see note below in respect to the train staff). Until the lineman arrives and the instrument has been adjusted no train must be allowed to travel over the sec- tion affected, except in accordance with the instructions for working by pilotman (see rule 407). Note. — Should it be necessary to remove a second staff to put the instrument in phase, the lineman must take such second staff and lock it up until the damaged staff is repaired, when they must both be restored to the instrument where they are most needed. Should a train tablet or a train staff be damaged after it has been withdrawn and before it has gone forward into the section in advance, the train for which it has been withdrawn must not be detained for pilot-working, but must be sent away with the damaged staff, and the lineman at once sent for. Should a train tablet or train staff be lost, the single line working must be conducted by pilotman in accordance with rule 407 until every possible enquiry and search have been made for the missing tablet or staff, and, when it has been MACHINE BLOCKING FOR SINGLE TRACK LINES. 221 established beyond doubt that it cannot be found, the lineman must be sent for and the instrument adjusted by him so that the ordinary working may be resumed. In the event of the tablet or staff being afterwards found, it must be kept by the station-muster or other person in charge until the lineman can arrange to return it to the instrument. 402. In the event of an engine becoming disabled between two tablet or staff stations, the fireman must take the train tablet or train staff to the tablet or staff station from which assistance is most likely to be obtained, and, after in- forming the signal-man and showing him the tablet or staff, must personally hand it over to the driveV of the engine appointed to proceed to the assistance of the disabled engine, and accompany him to the place where he left his own engine, and the driver of the disabled engine must not allow his engine to be removed until the assisting engine has arrived. The driver of the assisting engine, after removing the disabled engine and the whole of the train (if the disabled engine was working a train) to the most convenient end of the section, must then hand over the tablet or staff to the signal-man or other authorized person, who must, when the de- scription of instrument in use makes this necessary, send it to the other end of the 222 BLOCK SIGNAL OPERATION. section, either by train or special engine, as may be required for the proper and expeditious working of the traffic. The fireman of the disabled engine must not on any account allow the train tablet or train staff to pass out of his possession until he hands it over to the driver of the assisting engine, and the driver of the assisting engine must not allow it to pass out of his possession until the disabled engine with the whole of the train (if any) is removed clear of the section, except when the line is obstructed and special arrangements are made for working in accordance with rule 403. The first train passing through the section after the line is again clear must be stopped, and the engine-driver instructed to proceed cautiously through the section. 403. Should an accident occur of such a nature as to obstruct the line, and the traffic is likely to be stopped for any considerable time, special arrangements must be made for working the trains to and from the tablet or staff station on each side of the point of obstruction. The train tablet or train staff must be retained to work trains between the point of obstruction and the tablet or staff station from which the tablet or staff was issued, and, on the other side the traffic must be con- ducted by a pilotman, in accordance with the following instructions : MACHINE BLOCKING FOR SINGLE TBACK LINES. 223 The guard must put the engine-driver in charge of the point of obstruction, and go himself to the end of the section to which the train was proceeding and arrange for three or more, as may be necessary, o£ the printed forms provided for the purpose of establishing working by pilot-man during obstruction (see page 233 for specimen form) to be filled up ; one of these must be delivered to the signal- man in charge of the tablet or staff station where pilot working commences, the second must be retained by the pilot-man, and the third must be conveyed to the engine-driver in charge of the point of obstruction. The pilot-man must wear a distinctive badge which, until the regular badge can be obtained, must be a red flag tied round the left arm. So soon as he is satisfied that the arrangements are imderstood, trains may be allowed to go on to the single line under the control and by the permission of the pilotman. The guard must accompany the first train to the point of obstruction. The engine-driver, when put in charge, must hand the train tablet or train staff to the fireman, and instruct him to take it back to the tablet or staff station from which it was issued, to work trains between that station and the point of obstruction until the line is clear, when it must be dealt with in accordance with the instructions contained in rule 404. * * * * 224 BLOCK SIGNAL OPERATION. The line on each side of the obstraction must be protected in accordance with the rules, and the guard and fireman will be held responsible for taking care that this is done until men are appointed specially t«ing obstructed, the traffic between - and the place of obatmotion will be work^ by pilot-man in accordance with rules 4U.i and 404. 234 BLOCK SIGNAL OPERATION. will act u pilot-man, aud no engine or train ia to be allowed to paaa on to the aeotion where the obstruction exiatp, nnleaa he is present and personally orders the engine or train to atart. This order Is to remain in force until withdrawn by the pilot-man. Signed To •Noted by At place of obstruction, tiiwa •Noted by Station or box TimeL •Noted by. -.,..■■■„ ..— .^.^..«— ^..-^ Fllot-man. * Tht se signaturm must be made on the copy held by the pQot-man. The above form must be filled up and used whenever it is temporarily neoeaaary. owing to obstructioa on a single line, to work the traffic by pilot-man. Six of these forma must be kept in a convenient place at each train tablet, or train staff station, so aa to be available at any moment, night or day. Before rUot-worUng is commenced, a copy of this form must be signed by the pemon in charge at each end of the section on which it Is intmded to establish pilot working, and be kept by the pilot-man. who must see that each of the men signing the form retains a copy for himself. In the event of a station-master himself acting as pilot-man, he must address and give the form to the pwson he leavea in chaise of hia station. StatioD-mastexB and other persons in charge reoeivintt this form will be held responsible that the inspectors, fore- men, signal-men, and others at their station, are immediately made acquainted with the circumstances, and are instructed in their neoeesary duties. On the other side of the obstruction the line will be worked by the train ataff or train tablet as directed in rule 408. Note. — The time at which this form is cancelled muAt be written across it. MACHINE BLOCKING FOB SINGLE TRACK LINES. 235 Form ot Pilot-inan*a 'f loket. (Fnot ot Tlokat.) RAILWAY. PILOT-MAN'S TICKET, To BB UssD nr Aooosdavob with Buub 407. Train JiTo. To the Ouard and Engine Driver: Tou are authorized to proceed from to Pilot-man following Signature of PUot-man.. Date 236 BLOCK SIGNAL OPERATION. rBack of Ticket.) This ticket is to be giyen up by the Engine-driver immediately on axriTal, to tiie person in charge of the Tablet or Staff Station to which he is authorized to proceed, to be dealt with as the latter may be instmcted by the Superintendent of the Line. In addition to the bell code, given on page 86, the London & North Western Bailway uses bell signals as follows in working on the electric train staff system : 5-2. Belease staff for shunting. 2-5. Shunting completed. — Staff replaced. When it is necessary to withdraw a staff for shunting purposes on the single line the signal-man must give the prescribed bell signal, and when the shunting is completed and the single line is again clear, the staff must be restored to the instrument, and the prescribed signal " shunting completed — staff replaced " must be given to the staff station in advance. 1111 . Signal for adjusting 8ta&. MACHINE BLOCKING FOR SINGLE TRACK LINES. 237 In tlie event of the supply of train staffs at one end of the section becoming so reduced as to leave four only, and the number is likely to go on decreasing, owing to more trains having been dispatched in one direction than the other, the tele- graph lineman must be at once advised, in order that the necessary adjustment may be made, and he alone wiU be held responsible for performing the duty ; but it must not be done at places where there is a station-master, except in his presence. Before taking out the staffs, the telegraph lineman must advise the signal-man at the other end of the section of what he is about to do, by ringing 16 strokes on the bell (thus 4-4-4-4), which signal must be acknowledged. He must then unlock the instrument in the presence of the station-master and signal-man, and take out the number of staffs that he requires ; this must on every occasion be an even number (2-4-6-8-10, etc.) and under no circumstances must an odd number of staffs be transferred. The staffs withdrawn must be carefully strapped together. After taking out the requisite number, the lineman must replace the instrument in proper working order, and under no circumstances must he give one of the staffs in his possession to the driver of the train by which he travels. He must not permit any staff to be taken from the instrument, or any one to interfere with it while he is mak- 238 BLOCK SIGNAL OPERATION. ing the necessary adjustment, neither must he interfere with the instrument while a train is traveling in the section in either direction. On arrival of the train at the other end of the section, the signal-man there must first obtain the staff from the driver and place it in the instniment, and after noting the ntmiber of sta£G9 which the lineman has brought with him, the lineman must place these staffs also in the instrument through the slot in the usual waj. The telegraph lineman must record in the train roister at each end of the section the number of staffs transferred and the date ; and the signal-man at each end of the section must also confirm the number of staffs so removed and replaced by signing the entry made by the telegraph lineman in the train register, and inserting the time at which the transaction takes place. The entry must also be signed by the station-masters in the train register at their respective stations. The telegraph lineman must be specially careful that he does not lose any of the staffs in the process of transfer ; and, in order that the signal-man at each end of the section may be assured of this, the person in charge at the end of the section from which the sta£b are removed must send with the lineman a note stating how many stafib are being removed, and how many are left in the instrument. This note must be given to the person in charge at the other MACHINE BLOCKING FOR SINGLE TRACK LINES. 239 end, who must see that the number of stai& brought by the lineman corresponds with the number stated in the note, and that the totiJ number is accounted for, and make this clear to the signal-man. He must then send a telegraph or tele- phone message stating that the number is correct. When the staffs are replaced the instrument must be tested as provided bj the rules. When the staffs are reduced to four the signal-man, before sending for the line- man, must judge in what position the next few trains will place him, and he must defer sending for him until he is certain that his stafib will go on decreasing. It is important that when sending for the lineman he should be told for which section the stafib are running short. If the lineman arrives by train, and is going forward by the same train, he must not take out the surplus staffs until the signal- man has first obtained in the ordinary way the staff that the train will carry. 240 BLOCK SIGNAL OPERATION. INSTRUCTIONS GOVERNING THE OPERATION OF THE TRAIN STAFF SYSTEM ON THE CHICAGO, MILWAUKEE A ST. PAUL RAILWAY, BETWEEN SAVANNA AND SABULA JUNCTION. The Chicago, Wilwaukee k St. Paul Ry. has a single track part of its line, between Savanna, Ul., and Sabula, la., operated by the train staff system. The distance is about throe miles, and includes the bridge over the Mississippi River. The traffic is heavy, being rarely less than 50 trains per day, but it has not been thought expedient to double-track the line or to replace the bridge with a double- track structure. BUx'k working on the Webb and Thompson train staff system has therefore biM^n adopted in order to ensure facility and safety in handling the traffic. Facility in handling the traffic is of special importance in this case, the train movements being very irregular. The working of the train staff system is effected by the erection of a train staff pillar in the bUx'k signal offices at Savanna and another in the signal office at Sabula Junction ; ctvch pillar is in charge of the telegraph operator on duty. The MACHINE BLOCKING FOR SINGLE TRACK LINES. 241 two pillars are electrically connected, and it is impossible to operate one without the knowledge and co-operation of the operator in charge of the other. Each pillar is furnished with ten stafib for moving trains under absolute block. For moving trains under permissive block one pillar is furnished with one permissive train staff and six permissive tablets in addition to the ten regular stafib. The other pillar is fitted for the reception of the permissive staff and tablets which may be in w^hichever pillar necessity requires. A staff or tablet in the actual possession of the engine-man is the necessary authority for the movement of a train in either direction. Only one staff can be taken from a pillar at one time. When a staff has been withdrawn from one pillar another cannot be withdrawn from either until the staff previously removed has been placed in the same pillar or the one at the other end of the block. Absolute block in both directions is therefore effected. When permissive block is to be used the permissive staff is withdrawn from the pillar and used to unlock the box containing the permissive tablets. One tablet is given to each train, the last train taking the remaining tablets, if any, together with the permissive staff, or the permissive staff alone, if all the tablets have 242 BLOCK SIGNAL OPERATION. been used. Until the pennissiye staff and all the tablets have been placed in one of the pillars, no staff can be taken from either pillar. The following are the rules under which the operation is carried on : 1. No train or engine shall be run in either direction between Savanna and Sabula Junction unless the engine-man has in his possession a train staff or permis- sive tablet, which mubt be handed him by the conductor of his train and retained by him as long as his train or any portion of it is in the block. The possession of a staff or tablet is authority for the engine-man to proceed regardless of opposing trains, provided the block signal is in proper position and the conductor's signal has been given. 2. The conductor of a train or engine is the only person authorized to receive a train staff or tablet from the operator in charge, and must personally hand the same to the engine-man. On arrival at the opposite end of the block the conductor must obtain the stfiiff from the engine-man, and if all his train is within the station limits, personally deliver to the operator. 3. In case a train parts or it is necessary to double, the train staff or tablet must be retained by the engine-man until all the train is clear of the block. MACHINE BLOCKING FOR SINGLE TRACK LINES. 243 4. Before acceptdng a permissive tablet from the operator, conductors must know that the operator has the permissive staff in his possession. 5. Under no circumstances will a staff or tablet be transferred from one train to another. It must invariably be delivered to the operator strictly in accord- ance with these instructions. G. Engine-men who receive a regular staff willimderstand that all trains are clear of the block. They must be careful to note whether they have a regular or permissive staff. There is but one permissive staff. It differs in shape from the regular staff; is painted green and is marked ''permissive staff" 7. Engine-men who receive the permissive staff or a tablet will understand that the preceding train has not cleared the block, and must proceed cautiously. The block signal will be left at danger to trains running under permissive block, and the possession of the permissive staff or tablet is authority to pass the block signal at danger. 8. When two or more engines are coupled together the engine-man of the last engine, or the engine attached to the train, must carry the train staff or tablet, but 244 BLOCK SIGNAL OPERATION. the eDgine-man of the other engine must know that he has the staff or tablet before proceeding. 9. In case of failure of the staff apparatus, trains will be moved by special telegraph orders, as per general roles. 10. The upper arm or light of the block signal posts at Savanna and Sabula Junction governs Chicago & Council Bluffs division trains. The lower arm or light governs Dubuque division trains. 11. All rules relating to the protection of trains are in forre, and the general rules are only modified by the special instructions herein. 12. The telegraph operators at Savanna and Sabula Junction will have charge of the train staff pillars. The operator on duiy at Sabula Junction will r.ct as bridge dispatcher and have control of the traffic. He must keep himself in- formed in r^ard to the position of trains and be prepared to give important trains the preference. 13. When a train is to enter the block, under absolute block, the operator at the station from which it is to start will signal to the operator at the other end of the block, by one tap of the bell, that he wishes to withdraw a staff The opera- MACHINE BLOCKING FOR SINGLE TRACK LINES. 245 tor so signalled will reply with one tap of the bell and hold his key down until the needle shows, by returning to a vertical position, that a staff has been withdrawn, when he will release the key and turn the left indicator to " staff out." 14. On receipt of the bell tap the operator who is to withdraw the staff will turn the right hand indicator to " for staff," and withdraw a staff. When this is done he will turn the left hand indicator to " staff out " until the needle returns to a vertical position. The right hand indicator will return automatically to " for bell " when a staff is withdrawn. 15. When permissive block is to be used the operator in charge of the pillar which holds the permissive staff and tablets, will proceed in the same manner to withdraw the permissive staff as in the case of a regular stafl^ except that two taps of the bell will be used and acknowledged. The permissive staff will be used to unlock the box containing the permissive tablets and retained in the possession of the operator as per rule No. 19. 16. When a staff or tablet has been delivered to the conductor the proper block signal will be displayed, and on the departure of the train a record of the 246 BLOCK SIGNAL OPERATION. time of departure will be made on the block sheet and reported to operator at the other end, who will enter on his block sheet. 17. On arrival of the train at the opposite end of the block the conductor will deliver the staff or permissive tablet to the operator in chai^o, who wiU, after seeing the markers, record the arriving time of the train and report to the operator at the other end who will enter on his block sheet. 18. The operator receiving a staff will, after placing it in the pillar, torn the left indicator to " staff in." When a tablet is received the operator will not turn the indicator to '' staff in " until all the tablets and the permissive staff have been received, the tablets locked in the box and the permissive staff placed in the pillar. 19. The operator sending trains forward under permissive block must retain the permissive staff to be forwarded by the last train. If all the tablets have not been used in forwarding trains, the last train to use permissive block must take the remaining tablets and the permissive staff. 20. As conductors cannot accept tablets unless they see the permissive staff in the possession of the operator delivering the tablet, operator will keep the per- missive staff in view and call the attention of conductors to it. MACHINE BLOOEINQ FOR SINGLE TRACK LINES. 247 21. When the block is clear, the block signal should be placed at safety after the delivery of a staff to the conductor and immediately placed at danger on the departure of the train. 22. When using permissive block the block signal should remain at danger. 23. The operator must not deliver a staff or tablet to any person except the conductor of the train to enter the block. 24. Operators must not deliver a staff or tablet received from a train to another train imtil it has been passed through the pillar in strict accordance with the rules. 25. Under no consideration will an operator place a staff in the pillar or report a train to the operator at the other end as arrived until he has positively seen the marker and knows that all the train is inside the station limits. 26. Permissive block must not be used for the movement of passenger trains, except in case of emergency. 27. In case it is necessary to transfer the permissive staff and tablets from the pillar containing them to the other pillar, a train may be sent forward with all he permissive tablets and the permissive staff. 248 BLOCK SIGNAL OPERATION. 28. Should the staff apparatus fail the bridge dispatcher will more trains in the name of the east division train dispatcher as per general rules relating to the movement of trains by telegraph. 22 33 55 77 222 333 99 121 235 58 BT BSUi. 2 Taps, UnlodlL 3 " Staff in. 4 '' PexinismTe Tablet BeodTed. 5 " PenuuBLTe Tablets and Staff izi. BT TEEJtOSAPH. G. &, 0. B. Train No west, ready. ) Dnbnqne Train No west, ready. j Unlock for G. A G. B. Train Na East Unlock for Dnbuque Train No. East Let G. A G. B. Train No proceed nnder '^absolute** block. Let Dnbaqne Train No proceed nnder * \ abeolnte " block. Let G. & G. B. Train No. proceed under ''pemussiye'* block. Let Dnbnqne Train No. proceed nnder '^permissiTe^* block. Detiver all remaining tablets and the Permissive Staff to Train No. Hold west bound train. To be used by Savaima to notify Bridge DispfttolMr that a train is ready. To be used by Bridge Dlspatchi^r to direct Morement of Traira. MACHINE BLOCKING FOR SINGLE TEACK LINES, 249 The operator at Savanna must obtain authority from the bridge dispatcher for each train to go forward under permissive block before delivering the tablet or staff to the conductor. Operators must keep a correct record of the movement of trains on the sheet provided for that purpose. On that sheet must be entered the time each staff or tablet is deUvered, opposite the number of the train to which it was given, and the sheet must show whether the train went forward under absolute or permissive block CHAPTER XIV. APPENDIX. USE OF BLOCK SIGNALS FOB THE PBOTECTION OF MAINTENANCE-OF-WAT OPEBATIONS. Following are the instructions of the Midland Bailway of Englahd, for protect- ing maintenance-of-way operations by the use of fixed signals : *' When it is necessary to stop trains the foreman must supply the flagman with a red card, lettered as under, properly filled up, and the flagman must, on arriving at a signal box (signal station) hand the card to the signal-man, who must retain it, and act upon the instructions it contains imtil the card is withdrawn by the flagman under instructions of the foreman : \ n APPENDIX. ck mgnalling. 5 ** ** use of eleetrio bells 7 Introdnotion of Block Signalling into U. 8 8 Inyention of Sykes System 7 Semaphore Signal Introduced 22 Indicators 80, 90 *' Normal poedtipn of 90 Testing 129 " Use of 90 Interlocking at GrossingB and Junctions 50 " ErieB. B. roles. 76 '* minois B. B. & Warehouse OomnuBBion^s roles. 60 " Machines, Principles of ; 57 *' Signals, Definitions of 18 Junctions, Blocking at 8 ** Derail Switches at 51 ** Interlocked Signals at 50 Location of Distant Signals at 51 it INDEX. 265 it n (i (4 Junctions, London A North Western method of operating at 95 Operating Double Track 72 Triangular 75 Single and Double Track 73 Special Operating lastructions 52 Train going on main tracks at 142 Locking Listruments 163 ** Method of Operating 164 '* New York Central & Hudson Biver R. R. rules for operating 171 Machine Blocking 199 Chicago, Milwaukee & St. Paul Ry. rules for operating. 240 London A North Western Ry. " ** '* 207 Maintenance of Way Operations, Use of Block Signals in 250 Manual Blocking 8, 80 ** " ErieR. K. rules 136 '* ** Indicator. 80 ** " London & North Western Ry. rules 86 Mozier System .' 153 Normal Danger and Normal Safety Plans 185 Obstruction Danger Signal 106 Outlying Switches, Method of operating 160 t( it 266 na>sx. PAGlu Fusing Sidings, Blocking at 8 " *• Lap 158 Patenall System 165 Pilot Working, Electric Train Staff. 232 Erie'R. R. method 254 Power used for Automatic Block Signals 184 Rules, Chicago, MUwaukee & St. Paul Ry., for Electric Train Staff 240 Erie R. R., for Interlocking 76 *' ** Manual and OontroUed Manual Blocking. 136 Illinois Central R. R., for Electric Automatic Blocking 196 ** R. R. & Warehouse Commission, for Interlocking 60 Lake Shore & Mich. Southern Ry., for Electric Automatic Blocking 193 London & North Western Ry., for Electric Train Staff 207 ** " '* ** Manual Blocking 86 New York Central R. R., for Controlled Manual Blocking 171 New York, New Haven & Hartford R. R., for Outlying Switches 160 Pennsylvania R. R., for Electro-Pneumatio Automatic Blocking 189 Standard, Train Orders at Block Stations 48 '' Western Union TeL Co. , Relative to attaching Office Wires 40 Selector 28 Sidings, Lap 158 nn>Bx« 267 PAOK. Signals, Adyance, Looation of 25 '* Back Lights '. 29 *' Colors of 32 " Distant, Location of : 26 " Fixed, Normal Position 90 *' Hall 24, 190 '^ Homeand Distant on same post 31 '* Home, Location of 25 *• How to be regarded 27 *' Levers 28 *' Position of 27 " Repeater. 29 Semaphore 22 Testing Slotted Signals 130 •' Wires 28 Signal Lamps, Adjustment of Flame 35 Care of 36 Commutator. 29, 37 Construction of 35 Electric light 37 Pintsch gas 37 t 4 26fc INDEX. << C4 4( <( «t